diff options
Diffstat (limited to 'Lib/importlib')
| -rw-r--r-- | Lib/importlib/__init__.py | 178 | ||||
| -rw-r--r-- | Lib/importlib/_bootstrap.py | 1175 | ||||
| -rw-r--r-- | Lib/importlib/_bootstrap_external.py | 1641 | ||||
| -rw-r--r-- | Lib/importlib/abc.py | 388 | ||||
| -rw-r--r-- | Lib/importlib/machinery.py | 21 | ||||
| -rw-r--r-- | Lib/importlib/metadata.py | 528 | ||||
| -rw-r--r-- | Lib/importlib/resources.py | 259 | ||||
| -rw-r--r-- | Lib/importlib/util.py | 300 |
8 files changed, 20 insertions, 4470 deletions
diff --git a/Lib/importlib/__init__.py b/Lib/importlib/__init__.py index 0c73c50..ad31a1a 100644 --- a/Lib/importlib/__init__.py +++ b/Lib/importlib/__init__.py @@ -1,109 +1,20 @@ -"""A pure Python implementation of import.""" -__all__ = ['__import__', 'import_module', 'invalidate_caches', 'reload'] - -# Bootstrap help ##################################################### - -# Until bootstrapping is complete, DO NOT import any modules that attempt -# to import importlib._bootstrap (directly or indirectly). Since this -# partially initialised package would be present in sys.modules, those -# modules would get an uninitialised copy of the source version, instead -# of a fully initialised version (either the frozen one or the one -# initialised below if the frozen one is not available). -import _imp # Just the builtin component, NOT the full Python module +"""Backport of importlib.import_module from 3.x.""" +# While not critical (and in no way guaranteed!), it would be nice to keep this +# code compatible with Python 2.3. import sys -try: - import _frozen_importlib as _bootstrap -except ImportError: - from . import _bootstrap - _bootstrap._setup(sys, _imp) -else: - # importlib._bootstrap is the built-in import, ensure we don't create - # a second copy of the module. - _bootstrap.__name__ = 'importlib._bootstrap' - _bootstrap.__package__ = 'importlib' - try: - _bootstrap.__file__ = __file__.replace('__init__.py', '_bootstrap.py') - except NameError: - # __file__ is not guaranteed to be defined, e.g. if this code gets - # frozen by a tool like cx_Freeze. - pass - sys.modules['importlib._bootstrap'] = _bootstrap - -try: - import _frozen_importlib_external as _bootstrap_external -except ImportError: - from . import _bootstrap_external - _bootstrap_external._setup(_bootstrap) - _bootstrap._bootstrap_external = _bootstrap_external -else: - _bootstrap_external.__name__ = 'importlib._bootstrap_external' - _bootstrap_external.__package__ = 'importlib' - try: - _bootstrap_external.__file__ = __file__.replace('__init__.py', '_bootstrap_external.py') - except NameError: - # __file__ is not guaranteed to be defined, e.g. if this code gets - # frozen by a tool like cx_Freeze. - pass - sys.modules['importlib._bootstrap_external'] = _bootstrap_external - -# To simplify imports in test code -_pack_uint32 = _bootstrap_external._pack_uint32 -_unpack_uint32 = _bootstrap_external._unpack_uint32 - -# Fully bootstrapped at this point, import whatever you like, circular -# dependencies and startup overhead minimisation permitting :) - -import types -import warnings - - -# Public API ######################################################### - -from ._bootstrap import __import__ - - -def invalidate_caches(): - """Call the invalidate_caches() method on all meta path finders stored in - sys.meta_path (where implemented).""" - for finder in sys.meta_path: - if hasattr(finder, 'invalidate_caches'): - finder.invalidate_caches() - - -def find_loader(name, path=None): - """Return the loader for the specified module. - - This is a backward-compatible wrapper around find_spec(). - - This function is deprecated in favor of importlib.util.find_spec(). - - """ - warnings.warn('Deprecated since Python 3.4. ' - 'Use importlib.util.find_spec() instead.', - DeprecationWarning, stacklevel=2) - try: - loader = sys.modules[name].__loader__ - if loader is None: - raise ValueError('{}.__loader__ is None'.format(name)) - else: - return loader - except KeyError: - pass - except AttributeError: - raise ValueError('{}.__loader__ is not set'.format(name)) from None - - spec = _bootstrap._find_spec(name, path) - # We won't worry about malformed specs (missing attributes). - if spec is None: - return None - if spec.loader is None: - if spec.submodule_search_locations is None: - raise ImportError('spec for {} missing loader'.format(name), - name=name) - raise ImportError('namespace packages do not have loaders', - name=name) - return spec.loader +def _resolve_name(name, package, level): + """Return the absolute name of the module to be imported.""" + if not hasattr(package, 'rindex'): + raise ValueError("'package' not set to a string") + dot = len(package) + for x in xrange(level, 1, -1): + try: + dot = package.rindex('.', 0, dot) + except ValueError: + raise ValueError("attempted relative import beyond top-level " + "package") + return "%s.%s" % (package[:dot], name) def import_module(name, package=None): @@ -114,63 +25,14 @@ def import_module(name, package=None): relative import to an absolute import. """ - level = 0 if name.startswith('.'): if not package: - msg = ("the 'package' argument is required to perform a relative " - "import for {!r}") - raise TypeError(msg.format(name)) + raise TypeError("relative imports require the 'package' argument") + level = 0 for character in name: if character != '.': break level += 1 - return _bootstrap._gcd_import(name[level:], package, level) - - -_RELOADING = {} - - -def reload(module): - """Reload the module and return it. - - The module must have been successfully imported before. - - """ - if not module or not isinstance(module, types.ModuleType): - raise TypeError("reload() argument must be a module") - try: - name = module.__spec__.name - except AttributeError: - name = module.__name__ - - if sys.modules.get(name) is not module: - msg = "module {} not in sys.modules" - raise ImportError(msg.format(name), name=name) - if name in _RELOADING: - return _RELOADING[name] - _RELOADING[name] = module - try: - parent_name = name.rpartition('.')[0] - if parent_name: - try: - parent = sys.modules[parent_name] - except KeyError: - msg = "parent {!r} not in sys.modules" - raise ImportError(msg.format(parent_name), - name=parent_name) from None - else: - pkgpath = parent.__path__ - else: - pkgpath = None - target = module - spec = module.__spec__ = _bootstrap._find_spec(name, pkgpath, target) - if spec is None: - raise ModuleNotFoundError(f"spec not found for the module {name!r}", name=name) - _bootstrap._exec(spec, module) - # The module may have replaced itself in sys.modules! - return sys.modules[name] - finally: - try: - del _RELOADING[name] - except KeyError: - pass + name = _resolve_name(name[level:], package, level) + __import__(name) + return sys.modules[name] diff --git a/Lib/importlib/_bootstrap.py b/Lib/importlib/_bootstrap.py deleted file mode 100644 index 8de0e9e..0000000 --- a/Lib/importlib/_bootstrap.py +++ /dev/null @@ -1,1175 +0,0 @@ -"""Core implementation of import. - -This module is NOT meant to be directly imported! It has been designed such -that it can be bootstrapped into Python as the implementation of import. As -such it requires the injection of specific modules and attributes in order to -work. One should use importlib as the public-facing version of this module. - -""" -# -# IMPORTANT: Whenever making changes to this module, be sure to run a top-level -# `make regen-importlib` followed by `make` in order to get the frozen version -# of the module updated. Not doing so will result in the Makefile to fail for -# all others who don't have a ./python around to freeze the module -# in the early stages of compilation. -# - -# See importlib._setup() for what is injected into the global namespace. - -# When editing this code be aware that code executed at import time CANNOT -# reference any injected objects! This includes not only global code but also -# anything specified at the class level. - -# Bootstrap-related code ###################################################### - -_bootstrap_external = None - -def _wrap(new, old): - """Simple substitute for functools.update_wrapper.""" - for replace in ['__module__', '__name__', '__qualname__', '__doc__']: - if hasattr(old, replace): - setattr(new, replace, getattr(old, replace)) - new.__dict__.update(old.__dict__) - - -def _new_module(name): - return type(sys)(name) - - -# Module-level locking ######################################################## - -# A dict mapping module names to weakrefs of _ModuleLock instances -# Dictionary protected by the global import lock -_module_locks = {} -# A dict mapping thread ids to _ModuleLock instances -_blocking_on = {} - - -class _DeadlockError(RuntimeError): - pass - - -class _ModuleLock: - """A recursive lock implementation which is able to detect deadlocks - (e.g. thread 1 trying to take locks A then B, and thread 2 trying to - take locks B then A). - """ - - def __init__(self, name): - self.lock = _thread.allocate_lock() - self.wakeup = _thread.allocate_lock() - self.name = name - self.owner = None - self.count = 0 - self.waiters = 0 - - def has_deadlock(self): - # Deadlock avoidance for concurrent circular imports. - me = _thread.get_ident() - tid = self.owner - while True: - lock = _blocking_on.get(tid) - if lock is None: - return False - tid = lock.owner - if tid == me: - return True - - def acquire(self): - """ - Acquire the module lock. If a potential deadlock is detected, - a _DeadlockError is raised. - Otherwise, the lock is always acquired and True is returned. - """ - tid = _thread.get_ident() - _blocking_on[tid] = self - try: - while True: - with self.lock: - if self.count == 0 or self.owner == tid: - self.owner = tid - self.count += 1 - return True - if self.has_deadlock(): - raise _DeadlockError('deadlock detected by %r' % self) - if self.wakeup.acquire(False): - self.waiters += 1 - # Wait for a release() call - self.wakeup.acquire() - self.wakeup.release() - finally: - del _blocking_on[tid] - - def release(self): - tid = _thread.get_ident() - with self.lock: - if self.owner != tid: - raise RuntimeError('cannot release un-acquired lock') - assert self.count > 0 - self.count -= 1 - if self.count == 0: - self.owner = None - if self.waiters: - self.waiters -= 1 - self.wakeup.release() - - def __repr__(self): - return '_ModuleLock({!r}) at {}'.format(self.name, id(self)) - - -class _DummyModuleLock: - """A simple _ModuleLock equivalent for Python builds without - multi-threading support.""" - - def __init__(self, name): - self.name = name - self.count = 0 - - def acquire(self): - self.count += 1 - return True - - def release(self): - if self.count == 0: - raise RuntimeError('cannot release un-acquired lock') - self.count -= 1 - - def __repr__(self): - return '_DummyModuleLock({!r}) at {}'.format(self.name, id(self)) - - -class _ModuleLockManager: - - def __init__(self, name): - self._name = name - self._lock = None - - def __enter__(self): - self._lock = _get_module_lock(self._name) - self._lock.acquire() - - def __exit__(self, *args, **kwargs): - self._lock.release() - - -# The following two functions are for consumption by Python/import.c. - -def _get_module_lock(name): - """Get or create the module lock for a given module name. - - Acquire/release internally the global import lock to protect - _module_locks.""" - - _imp.acquire_lock() - try: - try: - lock = _module_locks[name]() - except KeyError: - lock = None - - if lock is None: - if _thread is None: - lock = _DummyModuleLock(name) - else: - lock = _ModuleLock(name) - - def cb(ref, name=name): - _imp.acquire_lock() - try: - # bpo-31070: Check if another thread created a new lock - # after the previous lock was destroyed - # but before the weakref callback was called. - if _module_locks.get(name) is ref: - del _module_locks[name] - finally: - _imp.release_lock() - - _module_locks[name] = _weakref.ref(lock, cb) - finally: - _imp.release_lock() - - return lock - - -def _lock_unlock_module(name): - """Acquires then releases the module lock for a given module name. - - This is used to ensure a module is completely initialized, in the - event it is being imported by another thread. - """ - lock = _get_module_lock(name) - try: - lock.acquire() - except _DeadlockError: - # Concurrent circular import, we'll accept a partially initialized - # module object. - pass - else: - lock.release() - -# Frame stripping magic ############################################### -def _call_with_frames_removed(f, *args, **kwds): - """remove_importlib_frames in import.c will always remove sequences - of importlib frames that end with a call to this function - - Use it instead of a normal call in places where including the importlib - frames introduces unwanted noise into the traceback (e.g. when executing - module code) - """ - return f(*args, **kwds) - - -def _verbose_message(message, *args, verbosity=1): - """Print the message to stderr if -v/PYTHONVERBOSE is turned on.""" - if sys.flags.verbose >= verbosity: - if not message.startswith(('#', 'import ')): - message = '# ' + message - print(message.format(*args), file=sys.stderr) - - -def _requires_builtin(fxn): - """Decorator to verify the named module is built-in.""" - def _requires_builtin_wrapper(self, fullname): - if fullname not in sys.builtin_module_names: - raise ImportError('{!r} is not a built-in module'.format(fullname), - name=fullname) - return fxn(self, fullname) - _wrap(_requires_builtin_wrapper, fxn) - return _requires_builtin_wrapper - - -def _requires_frozen(fxn): - """Decorator to verify the named module is frozen.""" - def _requires_frozen_wrapper(self, fullname): - if not _imp.is_frozen(fullname): - raise ImportError('{!r} is not a frozen module'.format(fullname), - name=fullname) - return fxn(self, fullname) - _wrap(_requires_frozen_wrapper, fxn) - return _requires_frozen_wrapper - - -# Typically used by loader classes as a method replacement. -def _load_module_shim(self, fullname): - """Load the specified module into sys.modules and return it. - - This method is deprecated. Use loader.exec_module instead. - - """ - spec = spec_from_loader(fullname, self) - if fullname in sys.modules: - module = sys.modules[fullname] - _exec(spec, module) - return sys.modules[fullname] - else: - return _load(spec) - -# Module specifications ####################################################### - -def _module_repr(module): - # The implementation of ModuleType.__repr__(). - loader = getattr(module, '__loader__', None) - if hasattr(loader, 'module_repr'): - # As soon as BuiltinImporter, FrozenImporter, and NamespaceLoader - # drop their implementations for module_repr. we can add a - # deprecation warning here. - try: - return loader.module_repr(module) - except Exception: - pass - try: - spec = module.__spec__ - except AttributeError: - pass - else: - if spec is not None: - return _module_repr_from_spec(spec) - - # We could use module.__class__.__name__ instead of 'module' in the - # various repr permutations. - try: - name = module.__name__ - except AttributeError: - name = '?' - try: - filename = module.__file__ - except AttributeError: - if loader is None: - return '<module {!r}>'.format(name) - else: - return '<module {!r} ({!r})>'.format(name, loader) - else: - return '<module {!r} from {!r}>'.format(name, filename) - - -class ModuleSpec: - """The specification for a module, used for loading. - - A module's spec is the source for information about the module. For - data associated with the module, including source, use the spec's - loader. - - `name` is the absolute name of the module. `loader` is the loader - to use when loading the module. `parent` is the name of the - package the module is in. The parent is derived from the name. - - `is_package` determines if the module is considered a package or - not. On modules this is reflected by the `__path__` attribute. - - `origin` is the specific location used by the loader from which to - load the module, if that information is available. When filename is - set, origin will match. - - `has_location` indicates that a spec's "origin" reflects a location. - When this is True, `__file__` attribute of the module is set. - - `cached` is the location of the cached bytecode file, if any. It - corresponds to the `__cached__` attribute. - - `submodule_search_locations` is the sequence of path entries to - search when importing submodules. If set, is_package should be - True--and False otherwise. - - Packages are simply modules that (may) have submodules. If a spec - has a non-None value in `submodule_search_locations`, the import - system will consider modules loaded from the spec as packages. - - Only finders (see importlib.abc.MetaPathFinder and - importlib.abc.PathEntryFinder) should modify ModuleSpec instances. - - """ - - def __init__(self, name, loader, *, origin=None, loader_state=None, - is_package=None): - self.name = name - self.loader = loader - self.origin = origin - self.loader_state = loader_state - self.submodule_search_locations = [] if is_package else None - - # file-location attributes - self._set_fileattr = False - self._cached = None - - def __repr__(self): - args = ['name={!r}'.format(self.name), - 'loader={!r}'.format(self.loader)] - if self.origin is not None: - args.append('origin={!r}'.format(self.origin)) - if self.submodule_search_locations is not None: - args.append('submodule_search_locations={}' - .format(self.submodule_search_locations)) - return '{}({})'.format(self.__class__.__name__, ', '.join(args)) - - def __eq__(self, other): - smsl = self.submodule_search_locations - try: - return (self.name == other.name and - self.loader == other.loader and - self.origin == other.origin and - smsl == other.submodule_search_locations and - self.cached == other.cached and - self.has_location == other.has_location) - except AttributeError: - return NotImplemented - - @property - def cached(self): - if self._cached is None: - if self.origin is not None and self._set_fileattr: - if _bootstrap_external is None: - raise NotImplementedError - self._cached = _bootstrap_external._get_cached(self.origin) - return self._cached - - @cached.setter - def cached(self, cached): - self._cached = cached - - @property - def parent(self): - """The name of the module's parent.""" - if self.submodule_search_locations is None: - return self.name.rpartition('.')[0] - else: - return self.name - - @property - def has_location(self): - return self._set_fileattr - - @has_location.setter - def has_location(self, value): - self._set_fileattr = bool(value) - - -def spec_from_loader(name, loader, *, origin=None, is_package=None): - """Return a module spec based on various loader methods.""" - if hasattr(loader, 'get_filename'): - if _bootstrap_external is None: - raise NotImplementedError - spec_from_file_location = _bootstrap_external.spec_from_file_location - - if is_package is None: - return spec_from_file_location(name, loader=loader) - search = [] if is_package else None - return spec_from_file_location(name, loader=loader, - submodule_search_locations=search) - - if is_package is None: - if hasattr(loader, 'is_package'): - try: - is_package = loader.is_package(name) - except ImportError: - is_package = None # aka, undefined - else: - # the default - is_package = False - - return ModuleSpec(name, loader, origin=origin, is_package=is_package) - - -def _spec_from_module(module, loader=None, origin=None): - # This function is meant for use in _setup(). - try: - spec = module.__spec__ - except AttributeError: - pass - else: - if spec is not None: - return spec - - name = module.__name__ - if loader is None: - try: - loader = module.__loader__ - except AttributeError: - # loader will stay None. - pass - try: - location = module.__file__ - except AttributeError: - location = None - if origin is None: - if location is None: - try: - origin = loader._ORIGIN - except AttributeError: - origin = None - else: - origin = location - try: - cached = module.__cached__ - except AttributeError: - cached = None - try: - submodule_search_locations = list(module.__path__) - except AttributeError: - submodule_search_locations = None - - spec = ModuleSpec(name, loader, origin=origin) - spec._set_fileattr = False if location is None else True - spec.cached = cached - spec.submodule_search_locations = submodule_search_locations - return spec - - -def _init_module_attrs(spec, module, *, override=False): - # The passed-in module may be not support attribute assignment, - # in which case we simply don't set the attributes. - # __name__ - if (override or getattr(module, '__name__', None) is None): - try: - module.__name__ = spec.name - except AttributeError: - pass - # __loader__ - if override or getattr(module, '__loader__', None) is None: - loader = spec.loader - if loader is None: - # A backward compatibility hack. - if spec.submodule_search_locations is not None: - if _bootstrap_external is None: - raise NotImplementedError - _NamespaceLoader = _bootstrap_external._NamespaceLoader - - loader = _NamespaceLoader.__new__(_NamespaceLoader) - loader._path = spec.submodule_search_locations - spec.loader = loader - # While the docs say that module.__file__ is not set for - # built-in modules, and the code below will avoid setting it if - # spec.has_location is false, this is incorrect for namespace - # packages. Namespace packages have no location, but their - # __spec__.origin is None, and thus their module.__file__ - # should also be None for consistency. While a bit of a hack, - # this is the best place to ensure this consistency. - # - # See # https://docs.python.org/3/library/importlib.html#importlib.abc.Loader.load_module - # and bpo-32305 - module.__file__ = None - try: - module.__loader__ = loader - except AttributeError: - pass - # __package__ - if override or getattr(module, '__package__', None) is None: - try: - module.__package__ = spec.parent - except AttributeError: - pass - # __spec__ - try: - module.__spec__ = spec - except AttributeError: - pass - # __path__ - if override or getattr(module, '__path__', None) is None: - if spec.submodule_search_locations is not None: - try: - module.__path__ = spec.submodule_search_locations - except AttributeError: - pass - # __file__/__cached__ - if spec.has_location: - if override or getattr(module, '__file__', None) is None: - try: - module.__file__ = spec.origin - except AttributeError: - pass - - if override or getattr(module, '__cached__', None) is None: - if spec.cached is not None: - try: - module.__cached__ = spec.cached - except AttributeError: - pass - return module - - -def module_from_spec(spec): - """Create a module based on the provided spec.""" - # Typically loaders will not implement create_module(). - module = None - if hasattr(spec.loader, 'create_module'): - # If create_module() returns `None` then it means default - # module creation should be used. - module = spec.loader.create_module(spec) - elif hasattr(spec.loader, 'exec_module'): - raise ImportError('loaders that define exec_module() ' - 'must also define create_module()') - if module is None: - module = _new_module(spec.name) - _init_module_attrs(spec, module) - return module - - -def _module_repr_from_spec(spec): - """Return the repr to use for the module.""" - # We mostly replicate _module_repr() using the spec attributes. - name = '?' if spec.name is None else spec.name - if spec.origin is None: - if spec.loader is None: - return '<module {!r}>'.format(name) - else: - return '<module {!r} ({!r})>'.format(name, spec.loader) - else: - if spec.has_location: - return '<module {!r} from {!r}>'.format(name, spec.origin) - else: - return '<module {!r} ({})>'.format(spec.name, spec.origin) - - -# Used by importlib.reload() and _load_module_shim(). -def _exec(spec, module): - """Execute the spec's specified module in an existing module's namespace.""" - name = spec.name - with _ModuleLockManager(name): - if sys.modules.get(name) is not module: - msg = 'module {!r} not in sys.modules'.format(name) - raise ImportError(msg, name=name) - try: - if spec.loader is None: - if spec.submodule_search_locations is None: - raise ImportError('missing loader', name=spec.name) - # Namespace package. - _init_module_attrs(spec, module, override=True) - else: - _init_module_attrs(spec, module, override=True) - if not hasattr(spec.loader, 'exec_module'): - # (issue19713) Once BuiltinImporter and ExtensionFileLoader - # have exec_module() implemented, we can add a deprecation - # warning here. - spec.loader.load_module(name) - else: - spec.loader.exec_module(module) - finally: - # Update the order of insertion into sys.modules for module - # clean-up at shutdown. - module = sys.modules.pop(spec.name) - sys.modules[spec.name] = module - return module - - -def _load_backward_compatible(spec): - # (issue19713) Once BuiltinImporter and ExtensionFileLoader - # have exec_module() implemented, we can add a deprecation - # warning here. - try: - spec.loader.load_module(spec.name) - except: - if spec.name in sys.modules: - module = sys.modules.pop(spec.name) - sys.modules[spec.name] = module - raise - # The module must be in sys.modules at this point! - # Move it to the end of sys.modules. - module = sys.modules.pop(spec.name) - sys.modules[spec.name] = module - if getattr(module, '__loader__', None) is None: - try: - module.__loader__ = spec.loader - except AttributeError: - pass - if getattr(module, '__package__', None) is None: - try: - # Since module.__path__ may not line up with - # spec.submodule_search_paths, we can't necessarily rely - # on spec.parent here. - module.__package__ = module.__name__ - if not hasattr(module, '__path__'): - module.__package__ = spec.name.rpartition('.')[0] - except AttributeError: - pass - if getattr(module, '__spec__', None) is None: - try: - module.__spec__ = spec - except AttributeError: - pass - return module - -def _load_unlocked(spec): - # A helper for direct use by the import system. - if spec.loader is not None: - # Not a namespace package. - if not hasattr(spec.loader, 'exec_module'): - return _load_backward_compatible(spec) - - module = module_from_spec(spec) - - # This must be done before putting the module in sys.modules - # (otherwise an optimization shortcut in import.c becomes - # wrong). - spec._initializing = True - try: - sys.modules[spec.name] = module - try: - if spec.loader is None: - if spec.submodule_search_locations is None: - raise ImportError('missing loader', name=spec.name) - # A namespace package so do nothing. - else: - spec.loader.exec_module(module) - except: - try: - del sys.modules[spec.name] - except KeyError: - pass - raise - # Move the module to the end of sys.modules. - # We don't ensure that the import-related module attributes get - # set in the sys.modules replacement case. Such modules are on - # their own. - module = sys.modules.pop(spec.name) - sys.modules[spec.name] = module - _verbose_message('import {!r} # {!r}', spec.name, spec.loader) - finally: - spec._initializing = False - - return module - -# A method used during testing of _load_unlocked() and by -# _load_module_shim(). -def _load(spec): - """Return a new module object, loaded by the spec's loader. - - The module is not added to its parent. - - If a module is already in sys.modules, that existing module gets - clobbered. - - """ - with _ModuleLockManager(spec.name): - return _load_unlocked(spec) - - -# Loaders ##################################################################### - -class BuiltinImporter: - - """Meta path import for built-in modules. - - All methods are either class or static methods to avoid the need to - instantiate the class. - - """ - - _ORIGIN = "built-in" - - @staticmethod - def module_repr(module): - """Return repr for the module. - - The method is deprecated. The import machinery does the job itself. - - """ - return f'<module {module.__name__!r} ({BuiltinImporter._ORIGIN})>' - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - if path is not None: - return None - if _imp.is_builtin(fullname): - return spec_from_loader(fullname, cls, origin=cls._ORIGIN) - else: - return None - - @classmethod - def find_module(cls, fullname, path=None): - """Find the built-in module. - - If 'path' is ever specified then the search is considered a failure. - - This method is deprecated. Use find_spec() instead. - - """ - spec = cls.find_spec(fullname, path) - return spec.loader if spec is not None else None - - @classmethod - def create_module(self, spec): - """Create a built-in module""" - if spec.name not in sys.builtin_module_names: - raise ImportError('{!r} is not a built-in module'.format(spec.name), - name=spec.name) - return _call_with_frames_removed(_imp.create_builtin, spec) - - @classmethod - def exec_module(self, module): - """Exec a built-in module""" - _call_with_frames_removed(_imp.exec_builtin, module) - - @classmethod - @_requires_builtin - def get_code(cls, fullname): - """Return None as built-in modules do not have code objects.""" - return None - - @classmethod - @_requires_builtin - def get_source(cls, fullname): - """Return None as built-in modules do not have source code.""" - return None - - @classmethod - @_requires_builtin - def is_package(cls, fullname): - """Return False as built-in modules are never packages.""" - return False - - load_module = classmethod(_load_module_shim) - - -class FrozenImporter: - - """Meta path import for frozen modules. - - All methods are either class or static methods to avoid the need to - instantiate the class. - - """ - - _ORIGIN = "frozen" - - @staticmethod - def module_repr(m): - """Return repr for the module. - - The method is deprecated. The import machinery does the job itself. - - """ - return '<module {!r} ({})>'.format(m.__name__, FrozenImporter._ORIGIN) - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - if _imp.is_frozen(fullname): - return spec_from_loader(fullname, cls, origin=cls._ORIGIN) - else: - return None - - @classmethod - def find_module(cls, fullname, path=None): - """Find a frozen module. - - This method is deprecated. Use find_spec() instead. - - """ - return cls if _imp.is_frozen(fullname) else None - - @classmethod - def create_module(cls, spec): - """Use default semantics for module creation.""" - - @staticmethod - def exec_module(module): - name = module.__spec__.name - if not _imp.is_frozen(name): - raise ImportError('{!r} is not a frozen module'.format(name), - name=name) - code = _call_with_frames_removed(_imp.get_frozen_object, name) - exec(code, module.__dict__) - - @classmethod - def load_module(cls, fullname): - """Load a frozen module. - - This method is deprecated. Use exec_module() instead. - - """ - return _load_module_shim(cls, fullname) - - @classmethod - @_requires_frozen - def get_code(cls, fullname): - """Return the code object for the frozen module.""" - return _imp.get_frozen_object(fullname) - - @classmethod - @_requires_frozen - def get_source(cls, fullname): - """Return None as frozen modules do not have source code.""" - return None - - @classmethod - @_requires_frozen - def is_package(cls, fullname): - """Return True if the frozen module is a package.""" - return _imp.is_frozen_package(fullname) - - -# Import itself ############################################################### - -class _ImportLockContext: - - """Context manager for the import lock.""" - - def __enter__(self): - """Acquire the import lock.""" - _imp.acquire_lock() - - def __exit__(self, exc_type, exc_value, exc_traceback): - """Release the import lock regardless of any raised exceptions.""" - _imp.release_lock() - - -def _resolve_name(name, package, level): - """Resolve a relative module name to an absolute one.""" - bits = package.rsplit('.', level - 1) - if len(bits) < level: - raise ImportError('attempted relative import beyond top-level package') - base = bits[0] - return '{}.{}'.format(base, name) if name else base - - -def _find_spec_legacy(finder, name, path): - # This would be a good place for a DeprecationWarning if - # we ended up going that route. - loader = finder.find_module(name, path) - if loader is None: - return None - return spec_from_loader(name, loader) - - -def _find_spec(name, path, target=None): - """Find a module's spec.""" - meta_path = sys.meta_path - if meta_path is None: - # PyImport_Cleanup() is running or has been called. - raise ImportError("sys.meta_path is None, Python is likely " - "shutting down") - - if not meta_path: - _warnings.warn('sys.meta_path is empty', ImportWarning) - - # We check sys.modules here for the reload case. While a passed-in - # target will usually indicate a reload there is no guarantee, whereas - # sys.modules provides one. - is_reload = name in sys.modules - for finder in meta_path: - with _ImportLockContext(): - try: - find_spec = finder.find_spec - except AttributeError: - spec = _find_spec_legacy(finder, name, path) - if spec is None: - continue - else: - spec = find_spec(name, path, target) - if spec is not None: - # The parent import may have already imported this module. - if not is_reload and name in sys.modules: - module = sys.modules[name] - try: - __spec__ = module.__spec__ - except AttributeError: - # We use the found spec since that is the one that - # we would have used if the parent module hadn't - # beaten us to the punch. - return spec - else: - if __spec__ is None: - return spec - else: - return __spec__ - else: - return spec - else: - return None - - -def _sanity_check(name, package, level): - """Verify arguments are "sane".""" - if not isinstance(name, str): - raise TypeError('module name must be str, not {}'.format(type(name))) - if level < 0: - raise ValueError('level must be >= 0') - if level > 0: - if not isinstance(package, str): - raise TypeError('__package__ not set to a string') - elif not package: - raise ImportError('attempted relative import with no known parent ' - 'package') - if not name and level == 0: - raise ValueError('Empty module name') - - -_ERR_MSG_PREFIX = 'No module named ' -_ERR_MSG = _ERR_MSG_PREFIX + '{!r}' - -def _find_and_load_unlocked(name, import_): - path = None - parent = name.rpartition('.')[0] - if parent: - if parent not in sys.modules: - _call_with_frames_removed(import_, parent) - # Crazy side-effects! - if name in sys.modules: - return sys.modules[name] - parent_module = sys.modules[parent] - try: - path = parent_module.__path__ - except AttributeError: - msg = (_ERR_MSG + '; {!r} is not a package').format(name, parent) - raise ModuleNotFoundError(msg, name=name) from None - spec = _find_spec(name, path) - if spec is None: - raise ModuleNotFoundError(_ERR_MSG.format(name), name=name) - else: - module = _load_unlocked(spec) - if parent: - # Set the module as an attribute on its parent. - parent_module = sys.modules[parent] - setattr(parent_module, name.rpartition('.')[2], module) - return module - - -_NEEDS_LOADING = object() - - -def _find_and_load(name, import_): - """Find and load the module.""" - with _ModuleLockManager(name): - module = sys.modules.get(name, _NEEDS_LOADING) - if module is _NEEDS_LOADING: - return _find_and_load_unlocked(name, import_) - - if module is None: - message = ('import of {} halted; ' - 'None in sys.modules'.format(name)) - raise ModuleNotFoundError(message, name=name) - - _lock_unlock_module(name) - return module - - -def _gcd_import(name, package=None, level=0): - """Import and return the module based on its name, the package the call is - being made from, and the level adjustment. - - This function represents the greatest common denominator of functionality - between import_module and __import__. This includes setting __package__ if - the loader did not. - - """ - _sanity_check(name, package, level) - if level > 0: - name = _resolve_name(name, package, level) - return _find_and_load(name, _gcd_import) - - -def _handle_fromlist(module, fromlist, import_, *, recursive=False): - """Figure out what __import__ should return. - - The import_ parameter is a callable which takes the name of module to - import. It is required to decouple the function from assuming importlib's - import implementation is desired. - - """ - # The hell that is fromlist ... - # If a package was imported, try to import stuff from fromlist. - for x in fromlist: - if not isinstance(x, str): - if recursive: - where = module.__name__ + '.__all__' - else: - where = "``from list''" - raise TypeError(f"Item in {where} must be str, " - f"not {type(x).__name__}") - elif x == '*': - if not recursive and hasattr(module, '__all__'): - _handle_fromlist(module, module.__all__, import_, - recursive=True) - elif not hasattr(module, x): - from_name = '{}.{}'.format(module.__name__, x) - try: - _call_with_frames_removed(import_, from_name) - except ModuleNotFoundError as exc: - # Backwards-compatibility dictates we ignore failed - # imports triggered by fromlist for modules that don't - # exist. - if (exc.name == from_name and - sys.modules.get(from_name, _NEEDS_LOADING) is not None): - continue - raise - return module - - -def _calc___package__(globals): - """Calculate what __package__ should be. - - __package__ is not guaranteed to be defined or could be set to None - to represent that its proper value is unknown. - - """ - package = globals.get('__package__') - spec = globals.get('__spec__') - if package is not None: - if spec is not None and package != spec.parent: - _warnings.warn("__package__ != __spec__.parent " - f"({package!r} != {spec.parent!r})", - ImportWarning, stacklevel=3) - return package - elif spec is not None: - return spec.parent - else: - _warnings.warn("can't resolve package from __spec__ or __package__, " - "falling back on __name__ and __path__", - ImportWarning, stacklevel=3) - package = globals['__name__'] - if '__path__' not in globals: - package = package.rpartition('.')[0] - return package - - -def __import__(name, globals=None, locals=None, fromlist=(), level=0): - """Import a module. - - The 'globals' argument is used to infer where the import is occurring from - to handle relative imports. The 'locals' argument is ignored. The - 'fromlist' argument specifies what should exist as attributes on the module - being imported (e.g. ``from module import <fromlist>``). The 'level' - argument represents the package location to import from in a relative - import (e.g. ``from ..pkg import mod`` would have a 'level' of 2). - - """ - if level == 0: - module = _gcd_import(name) - else: - globals_ = globals if globals is not None else {} - package = _calc___package__(globals_) - module = _gcd_import(name, package, level) - if not fromlist: - # Return up to the first dot in 'name'. This is complicated by the fact - # that 'name' may be relative. - if level == 0: - return _gcd_import(name.partition('.')[0]) - elif not name: - return module - else: - # Figure out where to slice the module's name up to the first dot - # in 'name'. - cut_off = len(name) - len(name.partition('.')[0]) - # Slice end needs to be positive to alleviate need to special-case - # when ``'.' not in name``. - return sys.modules[module.__name__[:len(module.__name__)-cut_off]] - elif hasattr(module, '__path__'): - return _handle_fromlist(module, fromlist, _gcd_import) - else: - return module - - -def _builtin_from_name(name): - spec = BuiltinImporter.find_spec(name) - if spec is None: - raise ImportError('no built-in module named ' + name) - return _load_unlocked(spec) - - -def _setup(sys_module, _imp_module): - """Setup importlib by importing needed built-in modules and injecting them - into the global namespace. - - As sys is needed for sys.modules access and _imp is needed to load built-in - modules, those two modules must be explicitly passed in. - - """ - global _imp, sys - _imp = _imp_module - sys = sys_module - - # Set up the spec for existing builtin/frozen modules. - module_type = type(sys) - for name, module in sys.modules.items(): - if isinstance(module, module_type): - if name in sys.builtin_module_names: - loader = BuiltinImporter - elif _imp.is_frozen(name): - loader = FrozenImporter - else: - continue - spec = _spec_from_module(module, loader) - _init_module_attrs(spec, module) - - # Directly load built-in modules needed during bootstrap. - self_module = sys.modules[__name__] - for builtin_name in ('_thread', '_warnings', '_weakref'): - if builtin_name not in sys.modules: - builtin_module = _builtin_from_name(builtin_name) - else: - builtin_module = sys.modules[builtin_name] - setattr(self_module, builtin_name, builtin_module) - - -def _install(sys_module, _imp_module): - """Install importers for builtin and frozen modules""" - _setup(sys_module, _imp_module) - - sys.meta_path.append(BuiltinImporter) - sys.meta_path.append(FrozenImporter) - - -def _install_external_importers(): - """Install importers that require external filesystem access""" - global _bootstrap_external - import _frozen_importlib_external - _bootstrap_external = _frozen_importlib_external - _frozen_importlib_external._install(sys.modules[__name__]) diff --git a/Lib/importlib/_bootstrap_external.py b/Lib/importlib/_bootstrap_external.py deleted file mode 100644 index d62c6cb..0000000 --- a/Lib/importlib/_bootstrap_external.py +++ /dev/null @@ -1,1641 +0,0 @@ -"""Core implementation of path-based import. - -This module is NOT meant to be directly imported! It has been designed such -that it can be bootstrapped into Python as the implementation of import. As -such it requires the injection of specific modules and attributes in order to -work. One should use importlib as the public-facing version of this module. - -""" -# IMPORTANT: Whenever making changes to this module, be sure to run a top-level -# `make regen-importlib` followed by `make` in order to get the frozen version -# of the module updated. Not doing so will result in the Makefile to fail for -# all others who don't have a ./python around to freeze the module in the early -# stages of compilation. -# - -# See importlib._setup() for what is injected into the global namespace. - -# When editing this code be aware that code executed at import time CANNOT -# reference any injected objects! This includes not only global code but also -# anything specified at the class level. - -# Bootstrap-related code ###################################################### -_CASE_INSENSITIVE_PLATFORMS_STR_KEY = 'win', -_CASE_INSENSITIVE_PLATFORMS_BYTES_KEY = 'cygwin', 'darwin' -_CASE_INSENSITIVE_PLATFORMS = (_CASE_INSENSITIVE_PLATFORMS_BYTES_KEY - + _CASE_INSENSITIVE_PLATFORMS_STR_KEY) - - -def _make_relax_case(): - if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS): - if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS_STR_KEY): - key = 'PYTHONCASEOK' - else: - key = b'PYTHONCASEOK' - - def _relax_case(): - """True if filenames must be checked case-insensitively.""" - return key in _os.environ - else: - def _relax_case(): - """True if filenames must be checked case-insensitively.""" - return False - return _relax_case - - -def _pack_uint32(x): - """Convert a 32-bit integer to little-endian.""" - return (int(x) & 0xFFFFFFFF).to_bytes(4, 'little') - - -def _unpack_uint32(data): - """Convert 4 bytes in little-endian to an integer.""" - assert len(data) == 4 - return int.from_bytes(data, 'little') - -def _unpack_uint16(data): - """Convert 2 bytes in little-endian to an integer.""" - assert len(data) == 2 - return int.from_bytes(data, 'little') - - -def _path_join(*path_parts): - """Replacement for os.path.join().""" - return path_sep.join([part.rstrip(path_separators) - for part in path_parts if part]) - - -def _path_split(path): - """Replacement for os.path.split().""" - if len(path_separators) == 1: - front, _, tail = path.rpartition(path_sep) - return front, tail - for x in reversed(path): - if x in path_separators: - front, tail = path.rsplit(x, maxsplit=1) - return front, tail - return '', path - - -def _path_stat(path): - """Stat the path. - - Made a separate function to make it easier to override in experiments - (e.g. cache stat results). - - """ - return _os.stat(path) - - -def _path_is_mode_type(path, mode): - """Test whether the path is the specified mode type.""" - try: - stat_info = _path_stat(path) - except OSError: - return False - return (stat_info.st_mode & 0o170000) == mode - - -def _path_isfile(path): - """Replacement for os.path.isfile.""" - return _path_is_mode_type(path, 0o100000) - - -def _path_isdir(path): - """Replacement for os.path.isdir.""" - if not path: - path = _os.getcwd() - return _path_is_mode_type(path, 0o040000) - - -def _path_isabs(path): - """Replacement for os.path.isabs. - - Considers a Windows drive-relative path (no drive, but starts with slash) to - still be "absolute". - """ - return path.startswith(path_separators) or path[1:3] in _pathseps_with_colon - - -def _write_atomic(path, data, mode=0o666): - """Best-effort function to write data to a path atomically. - Be prepared to handle a FileExistsError if concurrent writing of the - temporary file is attempted.""" - # id() is used to generate a pseudo-random filename. - path_tmp = '{}.{}'.format(path, id(path)) - fd = _os.open(path_tmp, - _os.O_EXCL | _os.O_CREAT | _os.O_WRONLY, mode & 0o666) - try: - # We first write data to a temporary file, and then use os.replace() to - # perform an atomic rename. - with _io.FileIO(fd, 'wb') as file: - file.write(data) - _os.replace(path_tmp, path) - except OSError: - try: - _os.unlink(path_tmp) - except OSError: - pass - raise - - -_code_type = type(_write_atomic.__code__) - - -# Finder/loader utility code ############################################### - -# Magic word to reject .pyc files generated by other Python versions. -# It should change for each incompatible change to the bytecode. -# -# The value of CR and LF is incorporated so if you ever read or write -# a .pyc file in text mode the magic number will be wrong; also, the -# Apple MPW compiler swaps their values, botching string constants. -# -# There were a variety of old schemes for setting the magic number. -# The current working scheme is to increment the previous value by -# 10. -# -# Starting with the adoption of PEP 3147 in Python 3.2, every bump in magic -# number also includes a new "magic tag", i.e. a human readable string used -# to represent the magic number in __pycache__ directories. When you change -# the magic number, you must also set a new unique magic tag. Generally this -# can be named after the Python major version of the magic number bump, but -# it can really be anything, as long as it's different than anything else -# that's come before. The tags are included in the following table, starting -# with Python 3.2a0. -# -# Known values: -# Python 1.5: 20121 -# Python 1.5.1: 20121 -# Python 1.5.2: 20121 -# Python 1.6: 50428 -# Python 2.0: 50823 -# Python 2.0.1: 50823 -# Python 2.1: 60202 -# Python 2.1.1: 60202 -# Python 2.1.2: 60202 -# Python 2.2: 60717 -# Python 2.3a0: 62011 -# Python 2.3a0: 62021 -# Python 2.3a0: 62011 (!) -# Python 2.4a0: 62041 -# Python 2.4a3: 62051 -# Python 2.4b1: 62061 -# Python 2.5a0: 62071 -# Python 2.5a0: 62081 (ast-branch) -# Python 2.5a0: 62091 (with) -# Python 2.5a0: 62092 (changed WITH_CLEANUP opcode) -# Python 2.5b3: 62101 (fix wrong code: for x, in ...) -# Python 2.5b3: 62111 (fix wrong code: x += yield) -# Python 2.5c1: 62121 (fix wrong lnotab with for loops and -# storing constants that should have been removed) -# Python 2.5c2: 62131 (fix wrong code: for x, in ... in listcomp/genexp) -# Python 2.6a0: 62151 (peephole optimizations and STORE_MAP opcode) -# Python 2.6a1: 62161 (WITH_CLEANUP optimization) -# Python 2.7a0: 62171 (optimize list comprehensions/change LIST_APPEND) -# Python 2.7a0: 62181 (optimize conditional branches: -# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE) -# Python 2.7a0 62191 (introduce SETUP_WITH) -# Python 2.7a0 62201 (introduce BUILD_SET) -# Python 2.7a0 62211 (introduce MAP_ADD and SET_ADD) -# Python 3000: 3000 -# 3010 (removed UNARY_CONVERT) -# 3020 (added BUILD_SET) -# 3030 (added keyword-only parameters) -# 3040 (added signature annotations) -# 3050 (print becomes a function) -# 3060 (PEP 3115 metaclass syntax) -# 3061 (string literals become unicode) -# 3071 (PEP 3109 raise changes) -# 3081 (PEP 3137 make __file__ and __name__ unicode) -# 3091 (kill str8 interning) -# 3101 (merge from 2.6a0, see 62151) -# 3103 (__file__ points to source file) -# Python 3.0a4: 3111 (WITH_CLEANUP optimization). -# Python 3.0b1: 3131 (lexical exception stacking, including POP_EXCEPT - #3021) -# Python 3.1a1: 3141 (optimize list, set and dict comprehensions: -# change LIST_APPEND and SET_ADD, add MAP_ADD #2183) -# Python 3.1a1: 3151 (optimize conditional branches: -# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE - #4715) -# Python 3.2a1: 3160 (add SETUP_WITH #6101) -# tag: cpython-32 -# Python 3.2a2: 3170 (add DUP_TOP_TWO, remove DUP_TOPX and ROT_FOUR #9225) -# tag: cpython-32 -# Python 3.2a3 3180 (add DELETE_DEREF #4617) -# Python 3.3a1 3190 (__class__ super closure changed) -# Python 3.3a1 3200 (PEP 3155 __qualname__ added #13448) -# Python 3.3a1 3210 (added size modulo 2**32 to the pyc header #13645) -# Python 3.3a2 3220 (changed PEP 380 implementation #14230) -# Python 3.3a4 3230 (revert changes to implicit __class__ closure #14857) -# Python 3.4a1 3250 (evaluate positional default arguments before -# keyword-only defaults #16967) -# Python 3.4a1 3260 (add LOAD_CLASSDEREF; allow locals of class to override -# free vars #17853) -# Python 3.4a1 3270 (various tweaks to the __class__ closure #12370) -# Python 3.4a1 3280 (remove implicit class argument) -# Python 3.4a4 3290 (changes to __qualname__ computation #19301) -# Python 3.4a4 3300 (more changes to __qualname__ computation #19301) -# Python 3.4rc2 3310 (alter __qualname__ computation #20625) -# Python 3.5a1 3320 (PEP 465: Matrix multiplication operator #21176) -# Python 3.5b1 3330 (PEP 448: Additional Unpacking Generalizations #2292) -# Python 3.5b2 3340 (fix dictionary display evaluation order #11205) -# Python 3.5b3 3350 (add GET_YIELD_FROM_ITER opcode #24400) -# Python 3.5.2 3351 (fix BUILD_MAP_UNPACK_WITH_CALL opcode #27286) -# Python 3.6a0 3360 (add FORMAT_VALUE opcode #25483) -# Python 3.6a1 3361 (lineno delta of code.co_lnotab becomes signed #26107) -# Python 3.6a2 3370 (16 bit wordcode #26647) -# Python 3.6a2 3371 (add BUILD_CONST_KEY_MAP opcode #27140) -# Python 3.6a2 3372 (MAKE_FUNCTION simplification, remove MAKE_CLOSURE -# #27095) -# Python 3.6b1 3373 (add BUILD_STRING opcode #27078) -# Python 3.6b1 3375 (add SETUP_ANNOTATIONS and STORE_ANNOTATION opcodes -# #27985) -# Python 3.6b1 3376 (simplify CALL_FUNCTIONs & BUILD_MAP_UNPACK_WITH_CALL - #27213) -# Python 3.6b1 3377 (set __class__ cell from type.__new__ #23722) -# Python 3.6b2 3378 (add BUILD_TUPLE_UNPACK_WITH_CALL #28257) -# Python 3.6rc1 3379 (more thorough __class__ validation #23722) -# Python 3.7a1 3390 (add LOAD_METHOD and CALL_METHOD opcodes #26110) -# Python 3.7a2 3391 (update GET_AITER #31709) -# Python 3.7a4 3392 (PEP 552: Deterministic pycs #31650) -# Python 3.7b1 3393 (remove STORE_ANNOTATION opcode #32550) -# Python 3.7b5 3394 (restored docstring as the first stmt in the body; -# this might affected the first line number #32911) -# Python 3.8a1 3400 (move frame block handling to compiler #17611) -# Python 3.8a1 3401 (add END_ASYNC_FOR #33041) -# Python 3.8a1 3410 (PEP570 Python Positional-Only Parameters #36540) -# Python 3.8b2 3411 (Reverse evaluation order of key: value in dict -# comprehensions #35224) -# Python 3.8b2 3412 (Swap the position of positional args and positional -# only args in ast.arguments #37593) -# Python 3.8b4 3413 (Fix "break" and "continue" in "finally" #37830) -# Python 3.9a0 3420 (add LOAD_ASSERTION_ERROR #34880) -# Python 3.9a0 3421 (simplified bytecode for with blocks #32949) -# Python 3.9a0 3422 (remove BEGIN_FINALLY, END_FINALLY, CALL_FINALLY, POP_FINALLY bytecodes #33387) -# -# MAGIC must change whenever the bytecode emitted by the compiler may no -# longer be understood by older implementations of the eval loop (usually -# due to the addition of new opcodes). -# -# Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array -# in PC/launcher.c must also be updated. - -MAGIC_NUMBER = (3422).to_bytes(2, 'little') + b'\r\n' -_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little') # For import.c - -_PYCACHE = '__pycache__' -_OPT = 'opt-' - -SOURCE_SUFFIXES = ['.py'] # _setup() adds .pyw as needed. - -BYTECODE_SUFFIXES = ['.pyc'] -# Deprecated. -DEBUG_BYTECODE_SUFFIXES = OPTIMIZED_BYTECODE_SUFFIXES = BYTECODE_SUFFIXES - -def cache_from_source(path, debug_override=None, *, optimization=None): - """Given the path to a .py file, return the path to its .pyc file. - - The .py file does not need to exist; this simply returns the path to the - .pyc file calculated as if the .py file were imported. - - The 'optimization' parameter controls the presumed optimization level of - the bytecode file. If 'optimization' is not None, the string representation - of the argument is taken and verified to be alphanumeric (else ValueError - is raised). - - The debug_override parameter is deprecated. If debug_override is not None, - a True value is the same as setting 'optimization' to the empty string - while a False value is equivalent to setting 'optimization' to '1'. - - If sys.implementation.cache_tag is None then NotImplementedError is raised. - - """ - if debug_override is not None: - _warnings.warn('the debug_override parameter is deprecated; use ' - "'optimization' instead", DeprecationWarning) - if optimization is not None: - message = 'debug_override or optimization must be set to None' - raise TypeError(message) - optimization = '' if debug_override else 1 - path = _os.fspath(path) - head, tail = _path_split(path) - base, sep, rest = tail.rpartition('.') - tag = sys.implementation.cache_tag - if tag is None: - raise NotImplementedError('sys.implementation.cache_tag is None') - almost_filename = ''.join([(base if base else rest), sep, tag]) - if optimization is None: - if sys.flags.optimize == 0: - optimization = '' - else: - optimization = sys.flags.optimize - optimization = str(optimization) - if optimization != '': - if not optimization.isalnum(): - raise ValueError('{!r} is not alphanumeric'.format(optimization)) - almost_filename = '{}.{}{}'.format(almost_filename, _OPT, optimization) - filename = almost_filename + BYTECODE_SUFFIXES[0] - if sys.pycache_prefix is not None: - # We need an absolute path to the py file to avoid the possibility of - # collisions within sys.pycache_prefix, if someone has two different - # `foo/bar.py` on their system and they import both of them using the - # same sys.pycache_prefix. Let's say sys.pycache_prefix is - # `C:\Bytecode`; the idea here is that if we get `Foo\Bar`, we first - # make it absolute (`C:\Somewhere\Foo\Bar`), then make it root-relative - # (`Somewhere\Foo\Bar`), so we end up placing the bytecode file in an - # unambiguous `C:\Bytecode\Somewhere\Foo\Bar\`. - if not _path_isabs(head): - head = _path_join(_os.getcwd(), head) - - # Strip initial drive from a Windows path. We know we have an absolute - # path here, so the second part of the check rules out a POSIX path that - # happens to contain a colon at the second character. - if head[1] == ':' and head[0] not in path_separators: - head = head[2:] - - # Strip initial path separator from `head` to complete the conversion - # back to a root-relative path before joining. - return _path_join( - sys.pycache_prefix, - head.lstrip(path_separators), - filename, - ) - return _path_join(head, _PYCACHE, filename) - - -def source_from_cache(path): - """Given the path to a .pyc. file, return the path to its .py file. - - The .pyc file does not need to exist; this simply returns the path to - the .py file calculated to correspond to the .pyc file. If path does - not conform to PEP 3147/488 format, ValueError will be raised. If - sys.implementation.cache_tag is None then NotImplementedError is raised. - - """ - if sys.implementation.cache_tag is None: - raise NotImplementedError('sys.implementation.cache_tag is None') - path = _os.fspath(path) - head, pycache_filename = _path_split(path) - found_in_pycache_prefix = False - if sys.pycache_prefix is not None: - stripped_path = sys.pycache_prefix.rstrip(path_separators) - if head.startswith(stripped_path + path_sep): - head = head[len(stripped_path):] - found_in_pycache_prefix = True - if not found_in_pycache_prefix: - head, pycache = _path_split(head) - if pycache != _PYCACHE: - raise ValueError(f'{_PYCACHE} not bottom-level directory in ' - f'{path!r}') - dot_count = pycache_filename.count('.') - if dot_count not in {2, 3}: - raise ValueError(f'expected only 2 or 3 dots in {pycache_filename!r}') - elif dot_count == 3: - optimization = pycache_filename.rsplit('.', 2)[-2] - if not optimization.startswith(_OPT): - raise ValueError("optimization portion of filename does not start " - f"with {_OPT!r}") - opt_level = optimization[len(_OPT):] - if not opt_level.isalnum(): - raise ValueError(f"optimization level {optimization!r} is not an " - "alphanumeric value") - base_filename = pycache_filename.partition('.')[0] - return _path_join(head, base_filename + SOURCE_SUFFIXES[0]) - - -def _get_sourcefile(bytecode_path): - """Convert a bytecode file path to a source path (if possible). - - This function exists purely for backwards-compatibility for - PyImport_ExecCodeModuleWithFilenames() in the C API. - - """ - if len(bytecode_path) == 0: - return None - rest, _, extension = bytecode_path.rpartition('.') - if not rest or extension.lower()[-3:-1] != 'py': - return bytecode_path - try: - source_path = source_from_cache(bytecode_path) - except (NotImplementedError, ValueError): - source_path = bytecode_path[:-1] - return source_path if _path_isfile(source_path) else bytecode_path - - -def _get_cached(filename): - if filename.endswith(tuple(SOURCE_SUFFIXES)): - try: - return cache_from_source(filename) - except NotImplementedError: - pass - elif filename.endswith(tuple(BYTECODE_SUFFIXES)): - return filename - else: - return None - - -def _calc_mode(path): - """Calculate the mode permissions for a bytecode file.""" - try: - mode = _path_stat(path).st_mode - except OSError: - mode = 0o666 - # We always ensure write access so we can update cached files - # later even when the source files are read-only on Windows (#6074) - mode |= 0o200 - return mode - - -def _check_name(method): - """Decorator to verify that the module being requested matches the one the - loader can handle. - - The first argument (self) must define _name which the second argument is - compared against. If the comparison fails then ImportError is raised. - - """ - def _check_name_wrapper(self, name=None, *args, **kwargs): - if name is None: - name = self.name - elif self.name != name: - raise ImportError('loader for %s cannot handle %s' % - (self.name, name), name=name) - return method(self, name, *args, **kwargs) - try: - _wrap = _bootstrap._wrap - except NameError: - # XXX yuck - def _wrap(new, old): - for replace in ['__module__', '__name__', '__qualname__', '__doc__']: - if hasattr(old, replace): - setattr(new, replace, getattr(old, replace)) - new.__dict__.update(old.__dict__) - _wrap(_check_name_wrapper, method) - return _check_name_wrapper - - -def _find_module_shim(self, fullname): - """Try to find a loader for the specified module by delegating to - self.find_loader(). - - This method is deprecated in favor of finder.find_spec(). - - """ - # Call find_loader(). If it returns a string (indicating this - # is a namespace package portion), generate a warning and - # return None. - loader, portions = self.find_loader(fullname) - if loader is None and len(portions): - msg = 'Not importing directory {}: missing __init__' - _warnings.warn(msg.format(portions[0]), ImportWarning) - return loader - - -def _classify_pyc(data, name, exc_details): - """Perform basic validity checking of a pyc header and return the flags field, - which determines how the pyc should be further validated against the source. - - *data* is the contents of the pyc file. (Only the first 16 bytes are - required, though.) - - *name* is the name of the module being imported. It is used for logging. - - *exc_details* is a dictionary passed to ImportError if it raised for - improved debugging. - - ImportError is raised when the magic number is incorrect or when the flags - field is invalid. EOFError is raised when the data is found to be truncated. - - """ - magic = data[:4] - if magic != MAGIC_NUMBER: - message = f'bad magic number in {name!r}: {magic!r}' - _bootstrap._verbose_message('{}', message) - raise ImportError(message, **exc_details) - if len(data) < 16: - message = f'reached EOF while reading pyc header of {name!r}' - _bootstrap._verbose_message('{}', message) - raise EOFError(message) - flags = _unpack_uint32(data[4:8]) - # Only the first two flags are defined. - if flags & ~0b11: - message = f'invalid flags {flags!r} in {name!r}' - raise ImportError(message, **exc_details) - return flags - - -def _validate_timestamp_pyc(data, source_mtime, source_size, name, - exc_details): - """Validate a pyc against the source last-modified time. - - *data* is the contents of the pyc file. (Only the first 16 bytes are - required.) - - *source_mtime* is the last modified timestamp of the source file. - - *source_size* is None or the size of the source file in bytes. - - *name* is the name of the module being imported. It is used for logging. - - *exc_details* is a dictionary passed to ImportError if it raised for - improved debugging. - - An ImportError is raised if the bytecode is stale. - - """ - if _unpack_uint32(data[8:12]) != (source_mtime & 0xFFFFFFFF): - message = f'bytecode is stale for {name!r}' - _bootstrap._verbose_message('{}', message) - raise ImportError(message, **exc_details) - if (source_size is not None and - _unpack_uint32(data[12:16]) != (source_size & 0xFFFFFFFF)): - raise ImportError(f'bytecode is stale for {name!r}', **exc_details) - - -def _validate_hash_pyc(data, source_hash, name, exc_details): - """Validate a hash-based pyc by checking the real source hash against the one in - the pyc header. - - *data* is the contents of the pyc file. (Only the first 16 bytes are - required.) - - *source_hash* is the importlib.util.source_hash() of the source file. - - *name* is the name of the module being imported. It is used for logging. - - *exc_details* is a dictionary passed to ImportError if it raised for - improved debugging. - - An ImportError is raised if the bytecode is stale. - - """ - if data[8:16] != source_hash: - raise ImportError( - f'hash in bytecode doesn\'t match hash of source {name!r}', - **exc_details, - ) - - -def _compile_bytecode(data, name=None, bytecode_path=None, source_path=None): - """Compile bytecode as found in a pyc.""" - code = marshal.loads(data) - if isinstance(code, _code_type): - _bootstrap._verbose_message('code object from {!r}', bytecode_path) - if source_path is not None: - _imp._fix_co_filename(code, source_path) - return code - else: - raise ImportError('Non-code object in {!r}'.format(bytecode_path), - name=name, path=bytecode_path) - - -def _code_to_timestamp_pyc(code, mtime=0, source_size=0): - "Produce the data for a timestamp-based pyc." - data = bytearray(MAGIC_NUMBER) - data.extend(_pack_uint32(0)) - data.extend(_pack_uint32(mtime)) - data.extend(_pack_uint32(source_size)) - data.extend(marshal.dumps(code)) - return data - - -def _code_to_hash_pyc(code, source_hash, checked=True): - "Produce the data for a hash-based pyc." - data = bytearray(MAGIC_NUMBER) - flags = 0b1 | checked << 1 - data.extend(_pack_uint32(flags)) - assert len(source_hash) == 8 - data.extend(source_hash) - data.extend(marshal.dumps(code)) - return data - - -def decode_source(source_bytes): - """Decode bytes representing source code and return the string. - - Universal newline support is used in the decoding. - """ - import tokenize # To avoid bootstrap issues. - source_bytes_readline = _io.BytesIO(source_bytes).readline - encoding = tokenize.detect_encoding(source_bytes_readline) - newline_decoder = _io.IncrementalNewlineDecoder(None, True) - return newline_decoder.decode(source_bytes.decode(encoding[0])) - - -# Module specifications ####################################################### - -_POPULATE = object() - - -def spec_from_file_location(name, location=None, *, loader=None, - submodule_search_locations=_POPULATE): - """Return a module spec based on a file location. - - To indicate that the module is a package, set - submodule_search_locations to a list of directory paths. An - empty list is sufficient, though its not otherwise useful to the - import system. - - The loader must take a spec as its only __init__() arg. - - """ - if location is None: - # The caller may simply want a partially populated location- - # oriented spec. So we set the location to a bogus value and - # fill in as much as we can. - location = '<unknown>' - if hasattr(loader, 'get_filename'): - # ExecutionLoader - try: - location = loader.get_filename(name) - except ImportError: - pass - else: - location = _os.fspath(location) - - # If the location is on the filesystem, but doesn't actually exist, - # we could return None here, indicating that the location is not - # valid. However, we don't have a good way of testing since an - # indirect location (e.g. a zip file or URL) will look like a - # non-existent file relative to the filesystem. - - spec = _bootstrap.ModuleSpec(name, loader, origin=location) - spec._set_fileattr = True - - # Pick a loader if one wasn't provided. - if loader is None: - for loader_class, suffixes in _get_supported_file_loaders(): - if location.endswith(tuple(suffixes)): - loader = loader_class(name, location) - spec.loader = loader - break - else: - return None - - # Set submodule_search_paths appropriately. - if submodule_search_locations is _POPULATE: - # Check the loader. - if hasattr(loader, 'is_package'): - try: - is_package = loader.is_package(name) - except ImportError: - pass - else: - if is_package: - spec.submodule_search_locations = [] - else: - spec.submodule_search_locations = submodule_search_locations - if spec.submodule_search_locations == []: - if location: - dirname = _path_split(location)[0] - spec.submodule_search_locations.append(dirname) - - return spec - - -# Loaders ##################################################################### - -class WindowsRegistryFinder: - - """Meta path finder for modules declared in the Windows registry.""" - - REGISTRY_KEY = ( - 'Software\\Python\\PythonCore\\{sys_version}' - '\\Modules\\{fullname}') - REGISTRY_KEY_DEBUG = ( - 'Software\\Python\\PythonCore\\{sys_version}' - '\\Modules\\{fullname}\\Debug') - DEBUG_BUILD = False # Changed in _setup() - - @classmethod - def _open_registry(cls, key): - try: - return _winreg.OpenKey(_winreg.HKEY_CURRENT_USER, key) - except OSError: - return _winreg.OpenKey(_winreg.HKEY_LOCAL_MACHINE, key) - - @classmethod - def _search_registry(cls, fullname): - if cls.DEBUG_BUILD: - registry_key = cls.REGISTRY_KEY_DEBUG - else: - registry_key = cls.REGISTRY_KEY - key = registry_key.format(fullname=fullname, - sys_version='%d.%d' % sys.version_info[:2]) - try: - with cls._open_registry(key) as hkey: - filepath = _winreg.QueryValue(hkey, '') - except OSError: - return None - return filepath - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - filepath = cls._search_registry(fullname) - if filepath is None: - return None - try: - _path_stat(filepath) - except OSError: - return None - for loader, suffixes in _get_supported_file_loaders(): - if filepath.endswith(tuple(suffixes)): - spec = _bootstrap.spec_from_loader(fullname, - loader(fullname, filepath), - origin=filepath) - return spec - - @classmethod - def find_module(cls, fullname, path=None): - """Find module named in the registry. - - This method is deprecated. Use exec_module() instead. - - """ - spec = cls.find_spec(fullname, path) - if spec is not None: - return spec.loader - else: - return None - - -class _LoaderBasics: - - """Base class of common code needed by both SourceLoader and - SourcelessFileLoader.""" - - def is_package(self, fullname): - """Concrete implementation of InspectLoader.is_package by checking if - the path returned by get_filename has a filename of '__init__.py'.""" - filename = _path_split(self.get_filename(fullname))[1] - filename_base = filename.rsplit('.', 1)[0] - tail_name = fullname.rpartition('.')[2] - return filename_base == '__init__' and tail_name != '__init__' - - def create_module(self, spec): - """Use default semantics for module creation.""" - - def exec_module(self, module): - """Execute the module.""" - code = self.get_code(module.__name__) - if code is None: - raise ImportError('cannot load module {!r} when get_code() ' - 'returns None'.format(module.__name__)) - _bootstrap._call_with_frames_removed(exec, code, module.__dict__) - - def load_module(self, fullname): - """This module is deprecated.""" - return _bootstrap._load_module_shim(self, fullname) - - -class SourceLoader(_LoaderBasics): - - def path_mtime(self, path): - """Optional method that returns the modification time (an int) for the - specified path (a str). - - Raises OSError when the path cannot be handled. - """ - raise OSError - - def path_stats(self, path): - """Optional method returning a metadata dict for the specified - path (a str). - - Possible keys: - - 'mtime' (mandatory) is the numeric timestamp of last source - code modification; - - 'size' (optional) is the size in bytes of the source code. - - Implementing this method allows the loader to read bytecode files. - Raises OSError when the path cannot be handled. - """ - return {'mtime': self.path_mtime(path)} - - def _cache_bytecode(self, source_path, cache_path, data): - """Optional method which writes data (bytes) to a file path (a str). - - Implementing this method allows for the writing of bytecode files. - - The source path is needed in order to correctly transfer permissions - """ - # For backwards compatibility, we delegate to set_data() - return self.set_data(cache_path, data) - - def set_data(self, path, data): - """Optional method which writes data (bytes) to a file path (a str). - - Implementing this method allows for the writing of bytecode files. - """ - - - def get_source(self, fullname): - """Concrete implementation of InspectLoader.get_source.""" - path = self.get_filename(fullname) - try: - source_bytes = self.get_data(path) - except OSError as exc: - raise ImportError('source not available through get_data()', - name=fullname) from exc - return decode_source(source_bytes) - - def source_to_code(self, data, path, *, _optimize=-1): - """Return the code object compiled from source. - - The 'data' argument can be any object type that compile() supports. - """ - return _bootstrap._call_with_frames_removed(compile, data, path, 'exec', - dont_inherit=True, optimize=_optimize) - - def get_code(self, fullname): - """Concrete implementation of InspectLoader.get_code. - - Reading of bytecode requires path_stats to be implemented. To write - bytecode, set_data must also be implemented. - - """ - source_path = self.get_filename(fullname) - source_mtime = None - source_bytes = None - source_hash = None - hash_based = False - check_source = True - try: - bytecode_path = cache_from_source(source_path) - except NotImplementedError: - bytecode_path = None - else: - try: - st = self.path_stats(source_path) - except OSError: - pass - else: - source_mtime = int(st['mtime']) - try: - data = self.get_data(bytecode_path) - except OSError: - pass - else: - exc_details = { - 'name': fullname, - 'path': bytecode_path, - } - try: - flags = _classify_pyc(data, fullname, exc_details) - bytes_data = memoryview(data)[16:] - hash_based = flags & 0b1 != 0 - if hash_based: - check_source = flags & 0b10 != 0 - if (_imp.check_hash_based_pycs != 'never' and - (check_source or - _imp.check_hash_based_pycs == 'always')): - source_bytes = self.get_data(source_path) - source_hash = _imp.source_hash( - _RAW_MAGIC_NUMBER, - source_bytes, - ) - _validate_hash_pyc(data, source_hash, fullname, - exc_details) - else: - _validate_timestamp_pyc( - data, - source_mtime, - st['size'], - fullname, - exc_details, - ) - except (ImportError, EOFError): - pass - else: - _bootstrap._verbose_message('{} matches {}', bytecode_path, - source_path) - return _compile_bytecode(bytes_data, name=fullname, - bytecode_path=bytecode_path, - source_path=source_path) - if source_bytes is None: - source_bytes = self.get_data(source_path) - code_object = self.source_to_code(source_bytes, source_path) - _bootstrap._verbose_message('code object from {}', source_path) - if (not sys.dont_write_bytecode and bytecode_path is not None and - source_mtime is not None): - if hash_based: - if source_hash is None: - source_hash = _imp.source_hash(source_bytes) - data = _code_to_hash_pyc(code_object, source_hash, check_source) - else: - data = _code_to_timestamp_pyc(code_object, source_mtime, - len(source_bytes)) - try: - self._cache_bytecode(source_path, bytecode_path, data) - except NotImplementedError: - pass - return code_object - - -class FileLoader: - - """Base file loader class which implements the loader protocol methods that - require file system usage.""" - - def __init__(self, fullname, path): - """Cache the module name and the path to the file found by the - finder.""" - self.name = fullname - self.path = path - - def __eq__(self, other): - return (self.__class__ == other.__class__ and - self.__dict__ == other.__dict__) - - def __hash__(self): - return hash(self.name) ^ hash(self.path) - - @_check_name - def load_module(self, fullname): - """Load a module from a file. - - This method is deprecated. Use exec_module() instead. - - """ - # The only reason for this method is for the name check. - # Issue #14857: Avoid the zero-argument form of super so the implementation - # of that form can be updated without breaking the frozen module - return super(FileLoader, self).load_module(fullname) - - @_check_name - def get_filename(self, fullname): - """Return the path to the source file as found by the finder.""" - return self.path - - def get_data(self, path): - """Return the data from path as raw bytes.""" - if isinstance(self, (SourceLoader, ExtensionFileLoader)): - with _io.open_code(str(path)) as file: - return file.read() - else: - with _io.FileIO(path, 'r') as file: - return file.read() - - # ResourceReader ABC API. - - @_check_name - def get_resource_reader(self, module): - if self.is_package(module): - return self - return None - - def open_resource(self, resource): - path = _path_join(_path_split(self.path)[0], resource) - return _io.FileIO(path, 'r') - - def resource_path(self, resource): - if not self.is_resource(resource): - raise FileNotFoundError - path = _path_join(_path_split(self.path)[0], resource) - return path - - def is_resource(self, name): - if path_sep in name: - return False - path = _path_join(_path_split(self.path)[0], name) - return _path_isfile(path) - - def contents(self): - return iter(_os.listdir(_path_split(self.path)[0])) - - -class SourceFileLoader(FileLoader, SourceLoader): - - """Concrete implementation of SourceLoader using the file system.""" - - def path_stats(self, path): - """Return the metadata for the path.""" - st = _path_stat(path) - return {'mtime': st.st_mtime, 'size': st.st_size} - - def _cache_bytecode(self, source_path, bytecode_path, data): - # Adapt between the two APIs - mode = _calc_mode(source_path) - return self.set_data(bytecode_path, data, _mode=mode) - - def set_data(self, path, data, *, _mode=0o666): - """Write bytes data to a file.""" - parent, filename = _path_split(path) - path_parts = [] - # Figure out what directories are missing. - while parent and not _path_isdir(parent): - parent, part = _path_split(parent) - path_parts.append(part) - # Create needed directories. - for part in reversed(path_parts): - parent = _path_join(parent, part) - try: - _os.mkdir(parent) - except FileExistsError: - # Probably another Python process already created the dir. - continue - except OSError as exc: - # Could be a permission error, read-only filesystem: just forget - # about writing the data. - _bootstrap._verbose_message('could not create {!r}: {!r}', - parent, exc) - return - try: - _write_atomic(path, data, _mode) - _bootstrap._verbose_message('created {!r}', path) - except OSError as exc: - # Same as above: just don't write the bytecode. - _bootstrap._verbose_message('could not create {!r}: {!r}', path, - exc) - - -class SourcelessFileLoader(FileLoader, _LoaderBasics): - - """Loader which handles sourceless file imports.""" - - def get_code(self, fullname): - path = self.get_filename(fullname) - data = self.get_data(path) - # Call _classify_pyc to do basic validation of the pyc but ignore the - # result. There's no source to check against. - exc_details = { - 'name': fullname, - 'path': path, - } - _classify_pyc(data, fullname, exc_details) - return _compile_bytecode( - memoryview(data)[16:], - name=fullname, - bytecode_path=path, - ) - - def get_source(self, fullname): - """Return None as there is no source code.""" - return None - - -# Filled in by _setup(). -EXTENSION_SUFFIXES = [] - - -class ExtensionFileLoader(FileLoader, _LoaderBasics): - - """Loader for extension modules. - - The constructor is designed to work with FileFinder. - - """ - - def __init__(self, name, path): - self.name = name - self.path = path - - def __eq__(self, other): - return (self.__class__ == other.__class__ and - self.__dict__ == other.__dict__) - - def __hash__(self): - return hash(self.name) ^ hash(self.path) - - def create_module(self, spec): - """Create an unitialized extension module""" - module = _bootstrap._call_with_frames_removed( - _imp.create_dynamic, spec) - _bootstrap._verbose_message('extension module {!r} loaded from {!r}', - spec.name, self.path) - return module - - def exec_module(self, module): - """Initialize an extension module""" - _bootstrap._call_with_frames_removed(_imp.exec_dynamic, module) - _bootstrap._verbose_message('extension module {!r} executed from {!r}', - self.name, self.path) - - def is_package(self, fullname): - """Return True if the extension module is a package.""" - file_name = _path_split(self.path)[1] - return any(file_name == '__init__' + suffix - for suffix in EXTENSION_SUFFIXES) - - def get_code(self, fullname): - """Return None as an extension module cannot create a code object.""" - return None - - def get_source(self, fullname): - """Return None as extension modules have no source code.""" - return None - - @_check_name - def get_filename(self, fullname): - """Return the path to the source file as found by the finder.""" - return self.path - - -class _NamespacePath: - """Represents a namespace package's path. It uses the module name - to find its parent module, and from there it looks up the parent's - __path__. When this changes, the module's own path is recomputed, - using path_finder. For top-level modules, the parent module's path - is sys.path.""" - - def __init__(self, name, path, path_finder): - self._name = name - self._path = path - self._last_parent_path = tuple(self._get_parent_path()) - self._path_finder = path_finder - - def _find_parent_path_names(self): - """Returns a tuple of (parent-module-name, parent-path-attr-name)""" - parent, dot, me = self._name.rpartition('.') - if dot == '': - # This is a top-level module. sys.path contains the parent path. - return 'sys', 'path' - # Not a top-level module. parent-module.__path__ contains the - # parent path. - return parent, '__path__' - - def _get_parent_path(self): - parent_module_name, path_attr_name = self._find_parent_path_names() - return getattr(sys.modules[parent_module_name], path_attr_name) - - def _recalculate(self): - # If the parent's path has changed, recalculate _path - parent_path = tuple(self._get_parent_path()) # Make a copy - if parent_path != self._last_parent_path: - spec = self._path_finder(self._name, parent_path) - # Note that no changes are made if a loader is returned, but we - # do remember the new parent path - if spec is not None and spec.loader is None: - if spec.submodule_search_locations: - self._path = spec.submodule_search_locations - self._last_parent_path = parent_path # Save the copy - return self._path - - def __iter__(self): - return iter(self._recalculate()) - - def __getitem__(self, index): - return self._recalculate()[index] - - def __setitem__(self, index, path): - self._path[index] = path - - def __len__(self): - return len(self._recalculate()) - - def __repr__(self): - return '_NamespacePath({!r})'.format(self._path) - - def __contains__(self, item): - return item in self._recalculate() - - def append(self, item): - self._path.append(item) - - -# We use this exclusively in module_from_spec() for backward-compatibility. -class _NamespaceLoader: - def __init__(self, name, path, path_finder): - self._path = _NamespacePath(name, path, path_finder) - - @classmethod - def module_repr(cls, module): - """Return repr for the module. - - The method is deprecated. The import machinery does the job itself. - - """ - return '<module {!r} (namespace)>'.format(module.__name__) - - def is_package(self, fullname): - return True - - def get_source(self, fullname): - return '' - - def get_code(self, fullname): - return compile('', '<string>', 'exec', dont_inherit=True) - - def create_module(self, spec): - """Use default semantics for module creation.""" - - def exec_module(self, module): - pass - - def load_module(self, fullname): - """Load a namespace module. - - This method is deprecated. Use exec_module() instead. - - """ - # The import system never calls this method. - _bootstrap._verbose_message('namespace module loaded with path {!r}', - self._path) - return _bootstrap._load_module_shim(self, fullname) - - -# Finders ##################################################################### - -class PathFinder: - - """Meta path finder for sys.path and package __path__ attributes.""" - - @classmethod - def invalidate_caches(cls): - """Call the invalidate_caches() method on all path entry finders - stored in sys.path_importer_caches (where implemented).""" - for name, finder in list(sys.path_importer_cache.items()): - if finder is None: - del sys.path_importer_cache[name] - elif hasattr(finder, 'invalidate_caches'): - finder.invalidate_caches() - - @classmethod - def _path_hooks(cls, path): - """Search sys.path_hooks for a finder for 'path'.""" - if sys.path_hooks is not None and not sys.path_hooks: - _warnings.warn('sys.path_hooks is empty', ImportWarning) - for hook in sys.path_hooks: - try: - return hook(path) - except ImportError: - continue - else: - return None - - @classmethod - def _path_importer_cache(cls, path): - """Get the finder for the path entry from sys.path_importer_cache. - - If the path entry is not in the cache, find the appropriate finder - and cache it. If no finder is available, store None. - - """ - if path == '': - try: - path = _os.getcwd() - except FileNotFoundError: - # Don't cache the failure as the cwd can easily change to - # a valid directory later on. - return None - try: - finder = sys.path_importer_cache[path] - except KeyError: - finder = cls._path_hooks(path) - sys.path_importer_cache[path] = finder - return finder - - @classmethod - def _legacy_get_spec(cls, fullname, finder): - # This would be a good place for a DeprecationWarning if - # we ended up going that route. - if hasattr(finder, 'find_loader'): - loader, portions = finder.find_loader(fullname) - else: - loader = finder.find_module(fullname) - portions = [] - if loader is not None: - return _bootstrap.spec_from_loader(fullname, loader) - spec = _bootstrap.ModuleSpec(fullname, None) - spec.submodule_search_locations = portions - return spec - - @classmethod - def _get_spec(cls, fullname, path, target=None): - """Find the loader or namespace_path for this module/package name.""" - # If this ends up being a namespace package, namespace_path is - # the list of paths that will become its __path__ - namespace_path = [] - for entry in path: - if not isinstance(entry, (str, bytes)): - continue - finder = cls._path_importer_cache(entry) - if finder is not None: - if hasattr(finder, 'find_spec'): - spec = finder.find_spec(fullname, target) - else: - spec = cls._legacy_get_spec(fullname, finder) - if spec is None: - continue - if spec.loader is not None: - return spec - portions = spec.submodule_search_locations - if portions is None: - raise ImportError('spec missing loader') - # This is possibly part of a namespace package. - # Remember these path entries (if any) for when we - # create a namespace package, and continue iterating - # on path. - namespace_path.extend(portions) - else: - spec = _bootstrap.ModuleSpec(fullname, None) - spec.submodule_search_locations = namespace_path - return spec - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - """Try to find a spec for 'fullname' on sys.path or 'path'. - - The search is based on sys.path_hooks and sys.path_importer_cache. - """ - if path is None: - path = sys.path - spec = cls._get_spec(fullname, path, target) - if spec is None: - return None - elif spec.loader is None: - namespace_path = spec.submodule_search_locations - if namespace_path: - # We found at least one namespace path. Return a spec which - # can create the namespace package. - spec.origin = None - spec.submodule_search_locations = _NamespacePath(fullname, namespace_path, cls._get_spec) - return spec - else: - return None - else: - return spec - - @classmethod - def find_module(cls, fullname, path=None): - """find the module on sys.path or 'path' based on sys.path_hooks and - sys.path_importer_cache. - - This method is deprecated. Use find_spec() instead. - - """ - spec = cls.find_spec(fullname, path) - if spec is None: - return None - return spec.loader - - @classmethod - def find_distributions(cls, *args, **kwargs): - """ - Find distributions. - - Return an iterable of all Distribution instances capable of - loading the metadata for packages matching ``context.name`` - (or all names if ``None`` indicated) along the paths in the list - of directories ``context.path``. - """ - from importlib.metadata import MetadataPathFinder - return MetadataPathFinder.find_distributions(*args, **kwargs) - - -class FileFinder: - - """File-based finder. - - Interactions with the file system are cached for performance, being - refreshed when the directory the finder is handling has been modified. - - """ - - def __init__(self, path, *loader_details): - """Initialize with the path to search on and a variable number of - 2-tuples containing the loader and the file suffixes the loader - recognizes.""" - loaders = [] - for loader, suffixes in loader_details: - loaders.extend((suffix, loader) for suffix in suffixes) - self._loaders = loaders - # Base (directory) path - self.path = path or '.' - self._path_mtime = -1 - self._path_cache = set() - self._relaxed_path_cache = set() - - def invalidate_caches(self): - """Invalidate the directory mtime.""" - self._path_mtime = -1 - - find_module = _find_module_shim - - def find_loader(self, fullname): - """Try to find a loader for the specified module, or the namespace - package portions. Returns (loader, list-of-portions). - - This method is deprecated. Use find_spec() instead. - - """ - spec = self.find_spec(fullname) - if spec is None: - return None, [] - return spec.loader, spec.submodule_search_locations or [] - - def _get_spec(self, loader_class, fullname, path, smsl, target): - loader = loader_class(fullname, path) - return spec_from_file_location(fullname, path, loader=loader, - submodule_search_locations=smsl) - - def find_spec(self, fullname, target=None): - """Try to find a spec for the specified module. - - Returns the matching spec, or None if not found. - """ - is_namespace = False - tail_module = fullname.rpartition('.')[2] - try: - mtime = _path_stat(self.path or _os.getcwd()).st_mtime - except OSError: - mtime = -1 - if mtime != self._path_mtime: - self._fill_cache() - self._path_mtime = mtime - # tail_module keeps the original casing, for __file__ and friends - if _relax_case(): - cache = self._relaxed_path_cache - cache_module = tail_module.lower() - else: - cache = self._path_cache - cache_module = tail_module - # Check if the module is the name of a directory (and thus a package). - if cache_module in cache: - base_path = _path_join(self.path, tail_module) - for suffix, loader_class in self._loaders: - init_filename = '__init__' + suffix - full_path = _path_join(base_path, init_filename) - if _path_isfile(full_path): - return self._get_spec(loader_class, fullname, full_path, [base_path], target) - else: - # If a namespace package, return the path if we don't - # find a module in the next section. - is_namespace = _path_isdir(base_path) - # Check for a file w/ a proper suffix exists. - for suffix, loader_class in self._loaders: - full_path = _path_join(self.path, tail_module + suffix) - _bootstrap._verbose_message('trying {}', full_path, verbosity=2) - if cache_module + suffix in cache: - if _path_isfile(full_path): - return self._get_spec(loader_class, fullname, full_path, - None, target) - if is_namespace: - _bootstrap._verbose_message('possible namespace for {}', base_path) - spec = _bootstrap.ModuleSpec(fullname, None) - spec.submodule_search_locations = [base_path] - return spec - return None - - def _fill_cache(self): - """Fill the cache of potential modules and packages for this directory.""" - path = self.path - try: - contents = _os.listdir(path or _os.getcwd()) - except (FileNotFoundError, PermissionError, NotADirectoryError): - # Directory has either been removed, turned into a file, or made - # unreadable. - contents = [] - # We store two cached versions, to handle runtime changes of the - # PYTHONCASEOK environment variable. - if not sys.platform.startswith('win'): - self._path_cache = set(contents) - else: - # Windows users can import modules with case-insensitive file - # suffixes (for legacy reasons). Make the suffix lowercase here - # so it's done once instead of for every import. This is safe as - # the specified suffixes to check against are always specified in a - # case-sensitive manner. - lower_suffix_contents = set() - for item in contents: - name, dot, suffix = item.partition('.') - if dot: - new_name = '{}.{}'.format(name, suffix.lower()) - else: - new_name = name - lower_suffix_contents.add(new_name) - self._path_cache = lower_suffix_contents - if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS): - self._relaxed_path_cache = {fn.lower() for fn in contents} - - @classmethod - def path_hook(cls, *loader_details): - """A class method which returns a closure to use on sys.path_hook - which will return an instance using the specified loaders and the path - called on the closure. - - If the path called on the closure is not a directory, ImportError is - raised. - - """ - def path_hook_for_FileFinder(path): - """Path hook for importlib.machinery.FileFinder.""" - if not _path_isdir(path): - raise ImportError('only directories are supported', path=path) - return cls(path, *loader_details) - - return path_hook_for_FileFinder - - def __repr__(self): - return 'FileFinder({!r})'.format(self.path) - - -# Import setup ############################################################### - -def _fix_up_module(ns, name, pathname, cpathname=None): - # This function is used by PyImport_ExecCodeModuleObject(). - loader = ns.get('__loader__') - spec = ns.get('__spec__') - if not loader: - if spec: - loader = spec.loader - elif pathname == cpathname: - loader = SourcelessFileLoader(name, pathname) - else: - loader = SourceFileLoader(name, pathname) - if not spec: - spec = spec_from_file_location(name, pathname, loader=loader) - try: - ns['__spec__'] = spec - ns['__loader__'] = loader - ns['__file__'] = pathname - ns['__cached__'] = cpathname - except Exception: - # Not important enough to report. - pass - - -def _get_supported_file_loaders(): - """Returns a list of file-based module loaders. - - Each item is a tuple (loader, suffixes). - """ - extensions = ExtensionFileLoader, _imp.extension_suffixes() - source = SourceFileLoader, SOURCE_SUFFIXES - bytecode = SourcelessFileLoader, BYTECODE_SUFFIXES - return [extensions, source, bytecode] - - -def _setup(_bootstrap_module): - """Setup the path-based importers for importlib by importing needed - built-in modules and injecting them into the global namespace. - - Other components are extracted from the core bootstrap module. - - """ - global sys, _imp, _bootstrap - _bootstrap = _bootstrap_module - sys = _bootstrap.sys - _imp = _bootstrap._imp - - # Directly load built-in modules needed during bootstrap. - self_module = sys.modules[__name__] - for builtin_name in ('_io', '_warnings', 'builtins', 'marshal'): - if builtin_name not in sys.modules: - builtin_module = _bootstrap._builtin_from_name(builtin_name) - else: - builtin_module = sys.modules[builtin_name] - setattr(self_module, builtin_name, builtin_module) - - # Directly load the os module (needed during bootstrap). - os_details = ('posix', ['/']), ('nt', ['\\', '/']) - for builtin_os, path_separators in os_details: - # Assumption made in _path_join() - assert all(len(sep) == 1 for sep in path_separators) - path_sep = path_separators[0] - if builtin_os in sys.modules: - os_module = sys.modules[builtin_os] - break - else: - try: - os_module = _bootstrap._builtin_from_name(builtin_os) - break - except ImportError: - continue - else: - raise ImportError('importlib requires posix or nt') - setattr(self_module, '_os', os_module) - setattr(self_module, 'path_sep', path_sep) - setattr(self_module, 'path_separators', ''.join(path_separators)) - setattr(self_module, '_pathseps_with_colon', {f':{s}' for s in path_separators}) - - # Directly load the _thread module (needed during bootstrap). - thread_module = _bootstrap._builtin_from_name('_thread') - setattr(self_module, '_thread', thread_module) - - # Directly load the _weakref module (needed during bootstrap). - weakref_module = _bootstrap._builtin_from_name('_weakref') - setattr(self_module, '_weakref', weakref_module) - - # Directly load the winreg module (needed during bootstrap). - if builtin_os == 'nt': - winreg_module = _bootstrap._builtin_from_name('winreg') - setattr(self_module, '_winreg', winreg_module) - - # Constants - setattr(self_module, '_relax_case', _make_relax_case()) - EXTENSION_SUFFIXES.extend(_imp.extension_suffixes()) - if builtin_os == 'nt': - SOURCE_SUFFIXES.append('.pyw') - if '_d.pyd' in EXTENSION_SUFFIXES: - WindowsRegistryFinder.DEBUG_BUILD = True - - -def _install(_bootstrap_module): - """Install the path-based import components.""" - _setup(_bootstrap_module) - supported_loaders = _get_supported_file_loaders() - sys.path_hooks.extend([FileFinder.path_hook(*supported_loaders)]) - sys.meta_path.append(PathFinder) diff --git a/Lib/importlib/abc.py b/Lib/importlib/abc.py deleted file mode 100644 index b1b5ccc..0000000 --- a/Lib/importlib/abc.py +++ /dev/null @@ -1,388 +0,0 @@ -"""Abstract base classes related to import.""" -from . import _bootstrap -from . import _bootstrap_external -from . import machinery -try: - import _frozen_importlib -except ImportError as exc: - if exc.name != '_frozen_importlib': - raise - _frozen_importlib = None -try: - import _frozen_importlib_external -except ImportError: - _frozen_importlib_external = _bootstrap_external -import abc -import warnings - - -def _register(abstract_cls, *classes): - for cls in classes: - abstract_cls.register(cls) - if _frozen_importlib is not None: - try: - frozen_cls = getattr(_frozen_importlib, cls.__name__) - except AttributeError: - frozen_cls = getattr(_frozen_importlib_external, cls.__name__) - abstract_cls.register(frozen_cls) - - -class Finder(metaclass=abc.ABCMeta): - - """Legacy abstract base class for import finders. - - It may be subclassed for compatibility with legacy third party - reimplementations of the import system. Otherwise, finder - implementations should derive from the more specific MetaPathFinder - or PathEntryFinder ABCs. - - Deprecated since Python 3.3 - """ - - @abc.abstractmethod - def find_module(self, fullname, path=None): - """An abstract method that should find a module. - The fullname is a str and the optional path is a str or None. - Returns a Loader object or None. - """ - - -class MetaPathFinder(Finder): - - """Abstract base class for import finders on sys.meta_path.""" - - # We don't define find_spec() here since that would break - # hasattr checks we do to support backward compatibility. - - def find_module(self, fullname, path): - """Return a loader for the module. - - If no module is found, return None. The fullname is a str and - the path is a list of strings or None. - - This method is deprecated since Python 3.4 in favor of - finder.find_spec(). If find_spec() exists then backwards-compatible - functionality is provided for this method. - - """ - warnings.warn("MetaPathFinder.find_module() is deprecated since Python " - "3.4 in favor of MetaPathFinder.find_spec() " - "(available since 3.4)", - DeprecationWarning, - stacklevel=2) - if not hasattr(self, 'find_spec'): - return None - found = self.find_spec(fullname, path) - return found.loader if found is not None else None - - def invalidate_caches(self): - """An optional method for clearing the finder's cache, if any. - This method is used by importlib.invalidate_caches(). - """ - -_register(MetaPathFinder, machinery.BuiltinImporter, machinery.FrozenImporter, - machinery.PathFinder, machinery.WindowsRegistryFinder) - - -class PathEntryFinder(Finder): - - """Abstract base class for path entry finders used by PathFinder.""" - - # We don't define find_spec() here since that would break - # hasattr checks we do to support backward compatibility. - - def find_loader(self, fullname): - """Return (loader, namespace portion) for the path entry. - - The fullname is a str. The namespace portion is a sequence of - path entries contributing to part of a namespace package. The - sequence may be empty. If loader is not None, the portion will - be ignored. - - The portion will be discarded if another path entry finder - locates the module as a normal module or package. - - This method is deprecated since Python 3.4 in favor of - finder.find_spec(). If find_spec() is provided than backwards-compatible - functionality is provided. - """ - warnings.warn("PathEntryFinder.find_loader() is deprecated since Python " - "3.4 in favor of PathEntryFinder.find_spec() " - "(available since 3.4)", - DeprecationWarning, - stacklevel=2) - if not hasattr(self, 'find_spec'): - return None, [] - found = self.find_spec(fullname) - if found is not None: - if not found.submodule_search_locations: - portions = [] - else: - portions = found.submodule_search_locations - return found.loader, portions - else: - return None, [] - - find_module = _bootstrap_external._find_module_shim - - def invalidate_caches(self): - """An optional method for clearing the finder's cache, if any. - This method is used by PathFinder.invalidate_caches(). - """ - -_register(PathEntryFinder, machinery.FileFinder) - - -class Loader(metaclass=abc.ABCMeta): - - """Abstract base class for import loaders.""" - - def create_module(self, spec): - """Return a module to initialize and into which to load. - - This method should raise ImportError if anything prevents it - from creating a new module. It may return None to indicate - that the spec should create the new module. - """ - # By default, defer to default semantics for the new module. - return None - - # We don't define exec_module() here since that would break - # hasattr checks we do to support backward compatibility. - - def load_module(self, fullname): - """Return the loaded module. - - The module must be added to sys.modules and have import-related - attributes set properly. The fullname is a str. - - ImportError is raised on failure. - - This method is deprecated in favor of loader.exec_module(). If - exec_module() exists then it is used to provide a backwards-compatible - functionality for this method. - - """ - if not hasattr(self, 'exec_module'): - raise ImportError - return _bootstrap._load_module_shim(self, fullname) - - def module_repr(self, module): - """Return a module's repr. - - Used by the module type when the method does not raise - NotImplementedError. - - This method is deprecated. - - """ - # The exception will cause ModuleType.__repr__ to ignore this method. - raise NotImplementedError - - -class ResourceLoader(Loader): - - """Abstract base class for loaders which can return data from their - back-end storage. - - This ABC represents one of the optional protocols specified by PEP 302. - - """ - - @abc.abstractmethod - def get_data(self, path): - """Abstract method which when implemented should return the bytes for - the specified path. The path must be a str.""" - raise OSError - - -class InspectLoader(Loader): - - """Abstract base class for loaders which support inspection about the - modules they can load. - - This ABC represents one of the optional protocols specified by PEP 302. - - """ - - def is_package(self, fullname): - """Optional method which when implemented should return whether the - module is a package. The fullname is a str. Returns a bool. - - Raises ImportError if the module cannot be found. - """ - raise ImportError - - def get_code(self, fullname): - """Method which returns the code object for the module. - - The fullname is a str. Returns a types.CodeType if possible, else - returns None if a code object does not make sense - (e.g. built-in module). Raises ImportError if the module cannot be - found. - """ - source = self.get_source(fullname) - if source is None: - return None - return self.source_to_code(source) - - @abc.abstractmethod - def get_source(self, fullname): - """Abstract method which should return the source code for the - module. The fullname is a str. Returns a str. - - Raises ImportError if the module cannot be found. - """ - raise ImportError - - @staticmethod - def source_to_code(data, path='<string>'): - """Compile 'data' into a code object. - - The 'data' argument can be anything that compile() can handle. The'path' - argument should be where the data was retrieved (when applicable).""" - return compile(data, path, 'exec', dont_inherit=True) - - exec_module = _bootstrap_external._LoaderBasics.exec_module - load_module = _bootstrap_external._LoaderBasics.load_module - -_register(InspectLoader, machinery.BuiltinImporter, machinery.FrozenImporter) - - -class ExecutionLoader(InspectLoader): - - """Abstract base class for loaders that wish to support the execution of - modules as scripts. - - This ABC represents one of the optional protocols specified in PEP 302. - - """ - - @abc.abstractmethod - def get_filename(self, fullname): - """Abstract method which should return the value that __file__ is to be - set to. - - Raises ImportError if the module cannot be found. - """ - raise ImportError - - def get_code(self, fullname): - """Method to return the code object for fullname. - - Should return None if not applicable (e.g. built-in module). - Raise ImportError if the module cannot be found. - """ - source = self.get_source(fullname) - if source is None: - return None - try: - path = self.get_filename(fullname) - except ImportError: - return self.source_to_code(source) - else: - return self.source_to_code(source, path) - -_register(ExecutionLoader, machinery.ExtensionFileLoader) - - -class FileLoader(_bootstrap_external.FileLoader, ResourceLoader, ExecutionLoader): - - """Abstract base class partially implementing the ResourceLoader and - ExecutionLoader ABCs.""" - -_register(FileLoader, machinery.SourceFileLoader, - machinery.SourcelessFileLoader) - - -class SourceLoader(_bootstrap_external.SourceLoader, ResourceLoader, ExecutionLoader): - - """Abstract base class for loading source code (and optionally any - corresponding bytecode). - - To support loading from source code, the abstractmethods inherited from - ResourceLoader and ExecutionLoader need to be implemented. To also support - loading from bytecode, the optional methods specified directly by this ABC - is required. - - Inherited abstractmethods not implemented in this ABC: - - * ResourceLoader.get_data - * ExecutionLoader.get_filename - - """ - - def path_mtime(self, path): - """Return the (int) modification time for the path (str).""" - if self.path_stats.__func__ is SourceLoader.path_stats: - raise OSError - return int(self.path_stats(path)['mtime']) - - def path_stats(self, path): - """Return a metadata dict for the source pointed to by the path (str). - Possible keys: - - 'mtime' (mandatory) is the numeric timestamp of last source - code modification; - - 'size' (optional) is the size in bytes of the source code. - """ - if self.path_mtime.__func__ is SourceLoader.path_mtime: - raise OSError - return {'mtime': self.path_mtime(path)} - - def set_data(self, path, data): - """Write the bytes to the path (if possible). - - Accepts a str path and data as bytes. - - Any needed intermediary directories are to be created. If for some - reason the file cannot be written because of permissions, fail - silently. - """ - -_register(SourceLoader, machinery.SourceFileLoader) - - -class ResourceReader(metaclass=abc.ABCMeta): - - """Abstract base class to provide resource-reading support. - - Loaders that support resource reading are expected to implement - the ``get_resource_reader(fullname)`` method and have it either return None - or an object compatible with this ABC. - """ - - @abc.abstractmethod - def open_resource(self, resource): - """Return an opened, file-like object for binary reading. - - The 'resource' argument is expected to represent only a file name - and thus not contain any subdirectory components. - - If the resource cannot be found, FileNotFoundError is raised. - """ - raise FileNotFoundError - - @abc.abstractmethod - def resource_path(self, resource): - """Return the file system path to the specified resource. - - The 'resource' argument is expected to represent only a file name - and thus not contain any subdirectory components. - - If the resource does not exist on the file system, raise - FileNotFoundError. - """ - raise FileNotFoundError - - @abc.abstractmethod - def is_resource(self, name): - """Return True if the named 'name' is consider a resource.""" - raise FileNotFoundError - - @abc.abstractmethod - def contents(self): - """Return an iterable of strings over the contents of the package.""" - return [] - - -_register(ResourceReader, machinery.SourceFileLoader) diff --git a/Lib/importlib/machinery.py b/Lib/importlib/machinery.py deleted file mode 100644 index 1b2b5c9..0000000 --- a/Lib/importlib/machinery.py +++ /dev/null @@ -1,21 +0,0 @@ -"""The machinery of importlib: finders, loaders, hooks, etc.""" - -import _imp - -from ._bootstrap import ModuleSpec -from ._bootstrap import BuiltinImporter -from ._bootstrap import FrozenImporter -from ._bootstrap_external import (SOURCE_SUFFIXES, DEBUG_BYTECODE_SUFFIXES, - OPTIMIZED_BYTECODE_SUFFIXES, BYTECODE_SUFFIXES, - EXTENSION_SUFFIXES) -from ._bootstrap_external import WindowsRegistryFinder -from ._bootstrap_external import PathFinder -from ._bootstrap_external import FileFinder -from ._bootstrap_external import SourceFileLoader -from ._bootstrap_external import SourcelessFileLoader -from ._bootstrap_external import ExtensionFileLoader - - -def all_suffixes(): - """Returns a list of all recognized module suffixes for this process""" - return SOURCE_SUFFIXES + BYTECODE_SUFFIXES + EXTENSION_SUFFIXES diff --git a/Lib/importlib/metadata.py b/Lib/importlib/metadata.py deleted file mode 100644 index 53f9fb5..0000000 --- a/Lib/importlib/metadata.py +++ /dev/null @@ -1,528 +0,0 @@ -import io -import os -import re -import abc -import csv -import sys -import email -import pathlib -import zipfile -import operator -import functools -import itertools -import collections - -from configparser import ConfigParser -from contextlib import suppress -from importlib import import_module -from importlib.abc import MetaPathFinder -from itertools import starmap - - -__all__ = [ - 'Distribution', - 'DistributionFinder', - 'PackageNotFoundError', - 'distribution', - 'distributions', - 'entry_points', - 'files', - 'metadata', - 'requires', - 'version', - ] - - -class PackageNotFoundError(ModuleNotFoundError): - """The package was not found.""" - - -class EntryPoint( - collections.namedtuple('EntryPointBase', 'name value group')): - """An entry point as defined by Python packaging conventions. - - See `the packaging docs on entry points - <https://packaging.python.org/specifications/entry-points/>`_ - for more information. - """ - - pattern = re.compile( - r'(?P<module>[\w.]+)\s*' - r'(:\s*(?P<attr>[\w.]+))?\s*' - r'(?P<extras>\[.*\])?\s*$' - ) - """ - A regular expression describing the syntax for an entry point, - which might look like: - - - module - - package.module - - package.module:attribute - - package.module:object.attribute - - package.module:attr [extra1, extra2] - - Other combinations are possible as well. - - The expression is lenient about whitespace around the ':', - following the attr, and following any extras. - """ - - def load(self): - """Load the entry point from its definition. If only a module - is indicated by the value, return that module. Otherwise, - return the named object. - """ - match = self.pattern.match(self.value) - module = import_module(match.group('module')) - attrs = filter(None, (match.group('attr') or '').split('.')) - return functools.reduce(getattr, attrs, module) - - @property - def extras(self): - match = self.pattern.match(self.value) - return list(re.finditer(r'\w+', match.group('extras') or '')) - - @classmethod - def _from_config(cls, config): - return [ - cls(name, value, group) - for group in config.sections() - for name, value in config.items(group) - ] - - @classmethod - def _from_text(cls, text): - config = ConfigParser(delimiters='=') - # case sensitive: https://stackoverflow.com/q/1611799/812183 - config.optionxform = str - try: - config.read_string(text) - except AttributeError: # pragma: nocover - # Python 2 has no read_string - config.readfp(io.StringIO(text)) - return EntryPoint._from_config(config) - - def __iter__(self): - """ - Supply iter so one may construct dicts of EntryPoints easily. - """ - return iter((self.name, self)) - - def __reduce__(self): - return ( - self.__class__, - (self.name, self.value, self.group), - ) - - -class PackagePath(pathlib.PurePosixPath): - """A reference to a path in a package""" - - def read_text(self, encoding='utf-8'): - with self.locate().open(encoding=encoding) as stream: - return stream.read() - - def read_binary(self): - with self.locate().open('rb') as stream: - return stream.read() - - def locate(self): - """Return a path-like object for this path""" - return self.dist.locate_file(self) - - -class FileHash: - def __init__(self, spec): - self.mode, _, self.value = spec.partition('=') - - def __repr__(self): - return '<FileHash mode: {} value: {}>'.format(self.mode, self.value) - - -class Distribution: - """A Python distribution package.""" - - @abc.abstractmethod - def read_text(self, filename): - """Attempt to load metadata file given by the name. - - :param filename: The name of the file in the distribution info. - :return: The text if found, otherwise None. - """ - - @abc.abstractmethod - def locate_file(self, path): - """ - Given a path to a file in this distribution, return a path - to it. - """ - - @classmethod - def from_name(cls, name): - """Return the Distribution for the given package name. - - :param name: The name of the distribution package to search for. - :return: The Distribution instance (or subclass thereof) for the named - package, if found. - :raises PackageNotFoundError: When the named package's distribution - metadata cannot be found. - """ - for resolver in cls._discover_resolvers(): - dists = resolver(DistributionFinder.Context(name=name)) - dist = next(dists, None) - if dist is not None: - return dist - else: - raise PackageNotFoundError(name) - - @classmethod - def discover(cls, **kwargs): - """Return an iterable of Distribution objects for all packages. - - Pass a ``context`` or pass keyword arguments for constructing - a context. - - :context: A ``DistributionFinder.Context`` object. - :return: Iterable of Distribution objects for all packages. - """ - context = kwargs.pop('context', None) - if context and kwargs: - raise ValueError("cannot accept context and kwargs") - context = context or DistributionFinder.Context(**kwargs) - return itertools.chain.from_iterable( - resolver(context) - for resolver in cls._discover_resolvers() - ) - - @staticmethod - def at(path): - """Return a Distribution for the indicated metadata path - - :param path: a string or path-like object - :return: a concrete Distribution instance for the path - """ - return PathDistribution(pathlib.Path(path)) - - @staticmethod - def _discover_resolvers(): - """Search the meta_path for resolvers.""" - declared = ( - getattr(finder, 'find_distributions', None) - for finder in sys.meta_path - ) - return filter(None, declared) - - @property - def metadata(self): - """Return the parsed metadata for this Distribution. - - The returned object will have keys that name the various bits of - metadata. See PEP 566 for details. - """ - text = ( - self.read_text('METADATA') - or self.read_text('PKG-INFO') - # This last clause is here to support old egg-info files. Its - # effect is to just end up using the PathDistribution's self._path - # (which points to the egg-info file) attribute unchanged. - or self.read_text('') - ) - return email.message_from_string(text) - - @property - def version(self): - """Return the 'Version' metadata for the distribution package.""" - return self.metadata['Version'] - - @property - def entry_points(self): - return EntryPoint._from_text(self.read_text('entry_points.txt')) - - @property - def files(self): - """Files in this distribution. - - :return: List of PackagePath for this distribution or None - - Result is `None` if the metadata file that enumerates files - (i.e. RECORD for dist-info or SOURCES.txt for egg-info) is - missing. - Result may be empty if the metadata exists but is empty. - """ - file_lines = self._read_files_distinfo() or self._read_files_egginfo() - - def make_file(name, hash=None, size_str=None): - result = PackagePath(name) - result.hash = FileHash(hash) if hash else None - result.size = int(size_str) if size_str else None - result.dist = self - return result - - return file_lines and list(starmap(make_file, csv.reader(file_lines))) - - def _read_files_distinfo(self): - """ - Read the lines of RECORD - """ - text = self.read_text('RECORD') - return text and text.splitlines() - - def _read_files_egginfo(self): - """ - SOURCES.txt might contain literal commas, so wrap each line - in quotes. - """ - text = self.read_text('SOURCES.txt') - return text and map('"{}"'.format, text.splitlines()) - - @property - def requires(self): - """Generated requirements specified for this Distribution""" - reqs = self._read_dist_info_reqs() or self._read_egg_info_reqs() - return reqs and list(reqs) - - def _read_dist_info_reqs(self): - return self.metadata.get_all('Requires-Dist') - - def _read_egg_info_reqs(self): - source = self.read_text('requires.txt') - return source and self._deps_from_requires_text(source) - - @classmethod - def _deps_from_requires_text(cls, source): - section_pairs = cls._read_sections(source.splitlines()) - sections = { - section: list(map(operator.itemgetter('line'), results)) - for section, results in - itertools.groupby(section_pairs, operator.itemgetter('section')) - } - return cls._convert_egg_info_reqs_to_simple_reqs(sections) - - @staticmethod - def _read_sections(lines): - section = None - for line in filter(None, lines): - section_match = re.match(r'\[(.*)\]$', line) - if section_match: - section = section_match.group(1) - continue - yield locals() - - @staticmethod - def _convert_egg_info_reqs_to_simple_reqs(sections): - """ - Historically, setuptools would solicit and store 'extra' - requirements, including those with environment markers, - in separate sections. More modern tools expect each - dependency to be defined separately, with any relevant - extras and environment markers attached directly to that - requirement. This method converts the former to the - latter. See _test_deps_from_requires_text for an example. - """ - def make_condition(name): - return name and 'extra == "{name}"'.format(name=name) - - def parse_condition(section): - section = section or '' - extra, sep, markers = section.partition(':') - if extra and markers: - markers = '({markers})'.format(markers=markers) - conditions = list(filter(None, [markers, make_condition(extra)])) - return '; ' + ' and '.join(conditions) if conditions else '' - - for section, deps in sections.items(): - for dep in deps: - yield dep + parse_condition(section) - - -class DistributionFinder(MetaPathFinder): - """ - A MetaPathFinder capable of discovering installed distributions. - """ - - class Context: - """ - Keyword arguments presented by the caller to - ``distributions()`` or ``Distribution.discover()`` - to narrow the scope of a search for distributions - in all DistributionFinders. - - Each DistributionFinder may expect any parameters - and should attempt to honor the canonical - parameters defined below when appropriate. - """ - - name = None - """ - Specific name for which a distribution finder should match. - A name of ``None`` matches all distributions. - """ - - def __init__(self, **kwargs): - vars(self).update(kwargs) - - @property - def path(self): - """ - The path that a distribution finder should search. - - Typically refers to Python package paths and defaults - to ``sys.path``. - """ - return vars(self).get('path', sys.path) - - @property - def pattern(self): - return '.*' if self.name is None else re.escape(self.name) - - @abc.abstractmethod - def find_distributions(self, context=Context()): - """ - Find distributions. - - Return an iterable of all Distribution instances capable of - loading the metadata for packages matching the ``context``, - a DistributionFinder.Context instance. - """ - - -class MetadataPathFinder(DistributionFinder): - @classmethod - def find_distributions(cls, context=DistributionFinder.Context()): - """ - Find distributions. - - Return an iterable of all Distribution instances capable of - loading the metadata for packages matching ``context.name`` - (or all names if ``None`` indicated) along the paths in the list - of directories ``context.path``. - """ - found = cls._search_paths(context.pattern, context.path) - return map(PathDistribution, found) - - @classmethod - def _search_paths(cls, pattern, paths): - """Find metadata directories in paths heuristically.""" - return itertools.chain.from_iterable( - cls._search_path(path, pattern) - for path in map(cls._switch_path, paths) - ) - - @staticmethod - def _switch_path(path): - PYPY_OPEN_BUG = False - if not PYPY_OPEN_BUG or os.path.isfile(path): # pragma: no branch - with suppress(Exception): - return zipfile.Path(path) - return pathlib.Path(path) - - @classmethod - def _matches_info(cls, normalized, item): - template = r'{pattern}(-.*)?\.(dist|egg)-info' - manifest = template.format(pattern=normalized) - return re.match(manifest, item.name, flags=re.IGNORECASE) - - @classmethod - def _matches_legacy(cls, normalized, item): - template = r'{pattern}-.*\.egg[\\/]EGG-INFO' - manifest = template.format(pattern=normalized) - return re.search(manifest, str(item), flags=re.IGNORECASE) - - @classmethod - def _search_path(cls, root, pattern): - if not root.is_dir(): - return () - normalized = pattern.replace('-', '_') - return (item for item in root.iterdir() - if cls._matches_info(normalized, item) - or cls._matches_legacy(normalized, item)) - - -class PathDistribution(Distribution): - def __init__(self, path): - """Construct a distribution from a path to the metadata directory. - - :param path: A pathlib.Path or similar object supporting - .joinpath(), __div__, .parent, and .read_text(). - """ - self._path = path - - def read_text(self, filename): - with suppress(FileNotFoundError, IsADirectoryError, KeyError, - NotADirectoryError, PermissionError): - return self._path.joinpath(filename).read_text(encoding='utf-8') - read_text.__doc__ = Distribution.read_text.__doc__ - - def locate_file(self, path): - return self._path.parent / path - - -def distribution(distribution_name): - """Get the ``Distribution`` instance for the named package. - - :param distribution_name: The name of the distribution package as a string. - :return: A ``Distribution`` instance (or subclass thereof). - """ - return Distribution.from_name(distribution_name) - - -def distributions(**kwargs): - """Get all ``Distribution`` instances in the current environment. - - :return: An iterable of ``Distribution`` instances. - """ - return Distribution.discover(**kwargs) - - -def metadata(distribution_name): - """Get the metadata for the named package. - - :param distribution_name: The name of the distribution package to query. - :return: An email.Message containing the parsed metadata. - """ - return Distribution.from_name(distribution_name).metadata - - -def version(distribution_name): - """Get the version string for the named package. - - :param distribution_name: The name of the distribution package to query. - :return: The version string for the package as defined in the package's - "Version" metadata key. - """ - return distribution(distribution_name).version - - -def entry_points(): - """Return EntryPoint objects for all installed packages. - - :return: EntryPoint objects for all installed packages. - """ - eps = itertools.chain.from_iterable( - dist.entry_points for dist in distributions()) - by_group = operator.attrgetter('group') - ordered = sorted(eps, key=by_group) - grouped = itertools.groupby(ordered, by_group) - return { - group: tuple(eps) - for group, eps in grouped - } - - -def files(distribution_name): - """Return a list of files for the named package. - - :param distribution_name: The name of the distribution package to query. - :return: List of files composing the distribution. - """ - return distribution(distribution_name).files - - -def requires(distribution_name): - """ - Return a list of requirements for the named package. - - :return: An iterator of requirements, suitable for - packaging.requirement.Requirement. - """ - return distribution(distribution_name).requires diff --git a/Lib/importlib/resources.py b/Lib/importlib/resources.py deleted file mode 100644 index fc3a1c9..0000000 --- a/Lib/importlib/resources.py +++ /dev/null @@ -1,259 +0,0 @@ -import os -import tempfile - -from . import abc as resources_abc -from contextlib import contextmanager, suppress -from importlib import import_module -from importlib.abc import ResourceLoader -from io import BytesIO, TextIOWrapper -from pathlib import Path -from types import ModuleType -from typing import Iterable, Iterator, Optional, Set, Union # noqa: F401 -from typing import cast -from typing.io import BinaryIO, TextIO -from zipimport import ZipImportError - - -__all__ = [ - 'Package', - 'Resource', - 'contents', - 'is_resource', - 'open_binary', - 'open_text', - 'path', - 'read_binary', - 'read_text', - ] - - -Package = Union[str, ModuleType] -Resource = Union[str, os.PathLike] - - -def _get_package(package) -> ModuleType: - """Take a package name or module object and return the module. - - If a name, the module is imported. If the passed or imported module - object is not a package, raise an exception. - """ - if hasattr(package, '__spec__'): - if package.__spec__.submodule_search_locations is None: - raise TypeError('{!r} is not a package'.format( - package.__spec__.name)) - else: - return package - else: - module = import_module(package) - if module.__spec__.submodule_search_locations is None: - raise TypeError('{!r} is not a package'.format(package)) - else: - return module - - -def _normalize_path(path) -> str: - """Normalize a path by ensuring it is a string. - - If the resulting string contains path separators, an exception is raised. - """ - parent, file_name = os.path.split(path) - if parent: - raise ValueError('{!r} must be only a file name'.format(path)) - else: - return file_name - - -def _get_resource_reader( - package: ModuleType) -> Optional[resources_abc.ResourceReader]: - # Return the package's loader if it's a ResourceReader. We can't use - # a issubclass() check here because apparently abc.'s __subclasscheck__() - # hook wants to create a weak reference to the object, but - # zipimport.zipimporter does not support weak references, resulting in a - # TypeError. That seems terrible. - spec = package.__spec__ - if hasattr(spec.loader, 'get_resource_reader'): - return cast(resources_abc.ResourceReader, - spec.loader.get_resource_reader(spec.name)) - return None - - -def _check_location(package): - if package.__spec__.origin is None or not package.__spec__.has_location: - raise FileNotFoundError(f'Package has no location {package!r}') - - -def open_binary(package: Package, resource: Resource) -> BinaryIO: - """Return a file-like object opened for binary reading of the resource.""" - resource = _normalize_path(resource) - package = _get_package(package) - reader = _get_resource_reader(package) - if reader is not None: - return reader.open_resource(resource) - _check_location(package) - absolute_package_path = os.path.abspath(package.__spec__.origin) - package_path = os.path.dirname(absolute_package_path) - full_path = os.path.join(package_path, resource) - try: - return open(full_path, mode='rb') - except OSError: - # Just assume the loader is a resource loader; all the relevant - # importlib.machinery loaders are and an AttributeError for - # get_data() will make it clear what is needed from the loader. - loader = cast(ResourceLoader, package.__spec__.loader) - data = None - if hasattr(package.__spec__.loader, 'get_data'): - with suppress(OSError): - data = loader.get_data(full_path) - if data is None: - package_name = package.__spec__.name - message = '{!r} resource not found in {!r}'.format( - resource, package_name) - raise FileNotFoundError(message) - else: - return BytesIO(data) - - -def open_text(package: Package, - resource: Resource, - encoding: str = 'utf-8', - errors: str = 'strict') -> TextIO: - """Return a file-like object opened for text reading of the resource.""" - resource = _normalize_path(resource) - package = _get_package(package) - reader = _get_resource_reader(package) - if reader is not None: - return TextIOWrapper(reader.open_resource(resource), encoding, errors) - _check_location(package) - absolute_package_path = os.path.abspath(package.__spec__.origin) - package_path = os.path.dirname(absolute_package_path) - full_path = os.path.join(package_path, resource) - try: - return open(full_path, mode='r', encoding=encoding, errors=errors) - except OSError: - # Just assume the loader is a resource loader; all the relevant - # importlib.machinery loaders are and an AttributeError for - # get_data() will make it clear what is needed from the loader. - loader = cast(ResourceLoader, package.__spec__.loader) - data = None - if hasattr(package.__spec__.loader, 'get_data'): - with suppress(OSError): - data = loader.get_data(full_path) - if data is None: - package_name = package.__spec__.name - message = '{!r} resource not found in {!r}'.format( - resource, package_name) - raise FileNotFoundError(message) - else: - return TextIOWrapper(BytesIO(data), encoding, errors) - - -def read_binary(package: Package, resource: Resource) -> bytes: - """Return the binary contents of the resource.""" - resource = _normalize_path(resource) - package = _get_package(package) - with open_binary(package, resource) as fp: - return fp.read() - - -def read_text(package: Package, - resource: Resource, - encoding: str = 'utf-8', - errors: str = 'strict') -> str: - """Return the decoded string of the resource. - - The decoding-related arguments have the same semantics as those of - bytes.decode(). - """ - resource = _normalize_path(resource) - package = _get_package(package) - with open_text(package, resource, encoding, errors) as fp: - return fp.read() - - -@contextmanager -def path(package: Package, resource: Resource) -> Iterator[Path]: - """A context manager providing a file path object to the resource. - - If the resource does not already exist on its own on the file system, - a temporary file will be created. If the file was created, the file - will be deleted upon exiting the context manager (no exception is - raised if the file was deleted prior to the context manager - exiting). - """ - resource = _normalize_path(resource) - package = _get_package(package) - reader = _get_resource_reader(package) - if reader is not None: - try: - yield Path(reader.resource_path(resource)) - return - except FileNotFoundError: - pass - else: - _check_location(package) - # Fall-through for both the lack of resource_path() *and* if - # resource_path() raises FileNotFoundError. - package_directory = Path(package.__spec__.origin).parent - file_path = package_directory / resource - if file_path.exists(): - yield file_path - else: - with open_binary(package, resource) as fp: - data = fp.read() - # Not using tempfile.NamedTemporaryFile as it leads to deeper 'try' - # blocks due to the need to close the temporary file to work on - # Windows properly. - fd, raw_path = tempfile.mkstemp() - try: - os.write(fd, data) - os.close(fd) - yield Path(raw_path) - finally: - try: - os.remove(raw_path) - except FileNotFoundError: - pass - - -def is_resource(package: Package, name: str) -> bool: - """True if 'name' is a resource inside 'package'. - - Directories are *not* resources. - """ - package = _get_package(package) - _normalize_path(name) - reader = _get_resource_reader(package) - if reader is not None: - return reader.is_resource(name) - try: - package_contents = set(contents(package)) - except (NotADirectoryError, FileNotFoundError): - return False - if name not in package_contents: - return False - # Just because the given file_name lives as an entry in the package's - # contents doesn't necessarily mean it's a resource. Directories are not - # resources, so let's try to find out if it's a directory or not. - path = Path(package.__spec__.origin).parent / name - return path.is_file() - - -def contents(package: Package) -> Iterable[str]: - """Return an iterable of entries in 'package'. - - Note that not all entries are resources. Specifically, directories are - not considered resources. Use `is_resource()` on each entry returned here - to check if it is a resource or not. - """ - package = _get_package(package) - reader = _get_resource_reader(package) - if reader is not None: - return reader.contents() - # Is the package a namespace package? By definition, namespace packages - # cannot have resources. We could use _check_location() and catch the - # exception, but that's extra work, so just inline the check. - elif package.__spec__.origin is None or not package.__spec__.has_location: - return () - else: - package_directory = Path(package.__spec__.origin).parent - return os.listdir(package_directory) diff --git a/Lib/importlib/util.py b/Lib/importlib/util.py deleted file mode 100644 index 269a6fa..0000000 --- a/Lib/importlib/util.py +++ /dev/null @@ -1,300 +0,0 @@ -"""Utility code for constructing importers, etc.""" -from . import abc -from ._bootstrap import module_from_spec -from ._bootstrap import _resolve_name -from ._bootstrap import spec_from_loader -from ._bootstrap import _find_spec -from ._bootstrap_external import MAGIC_NUMBER -from ._bootstrap_external import _RAW_MAGIC_NUMBER -from ._bootstrap_external import cache_from_source -from ._bootstrap_external import decode_source -from ._bootstrap_external import source_from_cache -from ._bootstrap_external import spec_from_file_location - -from contextlib import contextmanager -import _imp -import functools -import sys -import types -import warnings - - -def source_hash(source_bytes): - "Return the hash of *source_bytes* as used in hash-based pyc files." - return _imp.source_hash(_RAW_MAGIC_NUMBER, source_bytes) - - -def resolve_name(name, package): - """Resolve a relative module name to an absolute one.""" - if not name.startswith('.'): - return name - elif not package: - raise ImportError(f'no package specified for {repr(name)} ' - '(required for relative module names)') - level = 0 - for character in name: - if character != '.': - break - level += 1 - return _resolve_name(name[level:], package, level) - - -def _find_spec_from_path(name, path=None): - """Return the spec for the specified module. - - First, sys.modules is checked to see if the module was already imported. If - so, then sys.modules[name].__spec__ is returned. If that happens to be - set to None, then ValueError is raised. If the module is not in - sys.modules, then sys.meta_path is searched for a suitable spec with the - value of 'path' given to the finders. None is returned if no spec could - be found. - - Dotted names do not have their parent packages implicitly imported. You will - most likely need to explicitly import all parent packages in the proper - order for a submodule to get the correct spec. - - """ - if name not in sys.modules: - return _find_spec(name, path) - else: - module = sys.modules[name] - if module is None: - return None - try: - spec = module.__spec__ - except AttributeError: - raise ValueError('{}.__spec__ is not set'.format(name)) from None - else: - if spec is None: - raise ValueError('{}.__spec__ is None'.format(name)) - return spec - - -def find_spec(name, package=None): - """Return the spec for the specified module. - - First, sys.modules is checked to see if the module was already imported. If - so, then sys.modules[name].__spec__ is returned. If that happens to be - set to None, then ValueError is raised. If the module is not in - sys.modules, then sys.meta_path is searched for a suitable spec with the - value of 'path' given to the finders. None is returned if no spec could - be found. - - If the name is for submodule (contains a dot), the parent module is - automatically imported. - - The name and package arguments work the same as importlib.import_module(). - In other words, relative module names (with leading dots) work. - - """ - fullname = resolve_name(name, package) if name.startswith('.') else name - if fullname not in sys.modules: - parent_name = fullname.rpartition('.')[0] - if parent_name: - parent = __import__(parent_name, fromlist=['__path__']) - try: - parent_path = parent.__path__ - except AttributeError as e: - raise ModuleNotFoundError( - f"__path__ attribute not found on {parent_name!r} " - f"while trying to find {fullname!r}", name=fullname) from e - else: - parent_path = None - return _find_spec(fullname, parent_path) - else: - module = sys.modules[fullname] - if module is None: - return None - try: - spec = module.__spec__ - except AttributeError: - raise ValueError('{}.__spec__ is not set'.format(name)) from None - else: - if spec is None: - raise ValueError('{}.__spec__ is None'.format(name)) - return spec - - -@contextmanager -def _module_to_load(name): - is_reload = name in sys.modules - - module = sys.modules.get(name) - if not is_reload: - # This must be done before open() is called as the 'io' module - # implicitly imports 'locale' and would otherwise trigger an - # infinite loop. - module = type(sys)(name) - # This must be done before putting the module in sys.modules - # (otherwise an optimization shortcut in import.c becomes wrong) - module.__initializing__ = True - sys.modules[name] = module - try: - yield module - except Exception: - if not is_reload: - try: - del sys.modules[name] - except KeyError: - pass - finally: - module.__initializing__ = False - - -def set_package(fxn): - """Set __package__ on the returned module. - - This function is deprecated. - - """ - @functools.wraps(fxn) - def set_package_wrapper(*args, **kwargs): - warnings.warn('The import system now takes care of this automatically.', - DeprecationWarning, stacklevel=2) - module = fxn(*args, **kwargs) - if getattr(module, '__package__', None) is None: - module.__package__ = module.__name__ - if not hasattr(module, '__path__'): - module.__package__ = module.__package__.rpartition('.')[0] - return module - return set_package_wrapper - - -def set_loader(fxn): - """Set __loader__ on the returned module. - - This function is deprecated. - - """ - @functools.wraps(fxn) - def set_loader_wrapper(self, *args, **kwargs): - warnings.warn('The import system now takes care of this automatically.', - DeprecationWarning, stacklevel=2) - module = fxn(self, *args, **kwargs) - if getattr(module, '__loader__', None) is None: - module.__loader__ = self - return module - return set_loader_wrapper - - -def module_for_loader(fxn): - """Decorator to handle selecting the proper module for loaders. - - The decorated function is passed the module to use instead of the module - name. The module passed in to the function is either from sys.modules if - it already exists or is a new module. If the module is new, then __name__ - is set the first argument to the method, __loader__ is set to self, and - __package__ is set accordingly (if self.is_package() is defined) will be set - before it is passed to the decorated function (if self.is_package() does - not work for the module it will be set post-load). - - If an exception is raised and the decorator created the module it is - subsequently removed from sys.modules. - - The decorator assumes that the decorated function takes the module name as - the second argument. - - """ - warnings.warn('The import system now takes care of this automatically.', - DeprecationWarning, stacklevel=2) - @functools.wraps(fxn) - def module_for_loader_wrapper(self, fullname, *args, **kwargs): - with _module_to_load(fullname) as module: - module.__loader__ = self - try: - is_package = self.is_package(fullname) - except (ImportError, AttributeError): - pass - else: - if is_package: - module.__package__ = fullname - else: - module.__package__ = fullname.rpartition('.')[0] - # If __package__ was not set above, __import__() will do it later. - return fxn(self, module, *args, **kwargs) - - return module_for_loader_wrapper - - -class _LazyModule(types.ModuleType): - - """A subclass of the module type which triggers loading upon attribute access.""" - - def __getattribute__(self, attr): - """Trigger the load of the module and return the attribute.""" - # All module metadata must be garnered from __spec__ in order to avoid - # using mutated values. - # Stop triggering this method. - self.__class__ = types.ModuleType - # Get the original name to make sure no object substitution occurred - # in sys.modules. - original_name = self.__spec__.name - # Figure out exactly what attributes were mutated between the creation - # of the module and now. - attrs_then = self.__spec__.loader_state['__dict__'] - original_type = self.__spec__.loader_state['__class__'] - attrs_now = self.__dict__ - attrs_updated = {} - for key, value in attrs_now.items(): - # Code that set the attribute may have kept a reference to the - # assigned object, making identity more important than equality. - if key not in attrs_then: - attrs_updated[key] = value - elif id(attrs_now[key]) != id(attrs_then[key]): - attrs_updated[key] = value - self.__spec__.loader.exec_module(self) - # If exec_module() was used directly there is no guarantee the module - # object was put into sys.modules. - if original_name in sys.modules: - if id(self) != id(sys.modules[original_name]): - raise ValueError(f"module object for {original_name!r} " - "substituted in sys.modules during a lazy " - "load") - # Update after loading since that's what would happen in an eager - # loading situation. - self.__dict__.update(attrs_updated) - return getattr(self, attr) - - def __delattr__(self, attr): - """Trigger the load and then perform the deletion.""" - # To trigger the load and raise an exception if the attribute - # doesn't exist. - self.__getattribute__(attr) - delattr(self, attr) - - -class LazyLoader(abc.Loader): - - """A loader that creates a module which defers loading until attribute access.""" - - @staticmethod - def __check_eager_loader(loader): - if not hasattr(loader, 'exec_module'): - raise TypeError('loader must define exec_module()') - - @classmethod - def factory(cls, loader): - """Construct a callable which returns the eager loader made lazy.""" - cls.__check_eager_loader(loader) - return lambda *args, **kwargs: cls(loader(*args, **kwargs)) - - def __init__(self, loader): - self.__check_eager_loader(loader) - self.loader = loader - - def create_module(self, spec): - return self.loader.create_module(spec) - - def exec_module(self, module): - """Make the module load lazily.""" - module.__spec__.loader = self.loader - module.__loader__ = self.loader - # Don't need to worry about deep-copying as trying to set an attribute - # on an object would have triggered the load, - # e.g. ``module.__spec__.loader = None`` would trigger a load from - # trying to access module.__spec__. - loader_state = {} - loader_state['__dict__'] = module.__dict__.copy() - loader_state['__class__'] = module.__class__ - module.__spec__.loader_state = loader_state - module.__class__ = _LazyModule |